Bhagya

MP Board Class 12th General Hindi व्याकरण उपसर्ग

वे शब्दांश जो किसी शब्द में जुड़कर उसका अर्थ परिवर्तित कर देते हैं। उपसर्गों का कोई स्वतंत्र अस्तित्व नहीं होता; फिर भी वे अन्य शब्दों के साथ मिलकर एक विशेष अर्थ का बोध कराते हैं। उपसर्ग सदैव शब्द के पहले आता है, जैसे-‘परा’ उपसर्ग को ‘जय’ के पहले रखने से एक नया शब्द ‘पराजय’ बन जाता है। जिसका अर्थ होता है-हार।

उपसर्ग के शब्द में तीन प्रकार की स्थितियाँ उत्पन्न होती हैं।

जैसे-
1. शब्द के अर्थ में विपरीतता आ जाती है।
2. शब्द के अर्थ में नूतनता आ जाती है।
3. शब्द के अर्थ में कोई नया परिवर्तन नहीं होता।
उत्तर-
हिन्दी भाषा में उपसर्ग तीन भाषाओं के हैं
(a) संस्कृत उपसर्ग
(b) हिन्दी उपसर्ग
(c) उर्दू उपसर्ग।

(a) संस्कृत उपसर्ग

उपसर्ग के समान प्रयुक्त होने वाले कुछ अन्य शब्द

(b) हिन्दी उपसर्ग

(c) उर्दू उपसर्ग

MP Board Class 12th Hindi Solutions

MP Board Class 11th Special English Unseen Passages

MP Board Class 11th Special English Unseen Passage 1

CAMPS TO TAP CREATIVITY

1. As the dreaded examinations crawl to a halt, students look forward to the much-awaited “creative outlets”, the summer camps, to let off steam and spend their holidays. A summer camp is conducted over a short period of four to five weeks involving interesting filled activities. The colourful spectrum of summer-ramps- provides a wide variety of activities which include artistic skills, such as painting, origami, art, music, craft and also spoken English, cookery and computer courses. Not only this, the summer camps keep the child “fit as a fiddle” by imparting lessons in yoga, cricket, tennis and swimming.

2. With changing, times and trends parents have become productivity-oriented. They want their children to learn through productive play unlike in Lie past when play was just played. Today, the parents want to tap the potential of their children to the fullest. To achieve this aim, the summer camps afford an ideal opening for children to develop their hobbies and talents. The importance of creative play is often underestimated whereas the fact is ’that art and craft projects can excite even a young child’s imagination and promote a sense of great achievement. The little things that children make and take home give them a sense of achievement and pride when they show them to their parents.

3. Summer camps develop a child’s confidence and his ideas. They also encourage children to do things on their own. The camps are beneficial for hyperactive and aggressive children as they help channel their energies fruitfully by drawing out the best in them. They also promote mutual understanding not only among teachers and children but also bring about an interaction between the taught. This provides a good experience for a better future— a future of confidence.

(“The Young World” The Hindu)

Question 1.
On the basis of your reading of the passage complete the following sentences. Write the answers in your answer sheet against the.correct blank number :
(a) Activities in summer camps are …………………… and ……………………
(b) Summer camps keep the children healthy since ……………………
(c) Now-a-days parents think play should be ……………………
(d) “To achieve this aim”. What aim is the writer referring to here?
(e) “They also promote mutual understanding.” /They’ refers, …………………… to.
(f) Summer camps are particularly helpful for problem children who are …………………… and ……………………
Give the list of qualities (g) …………………… and (h) …………………… apart from the ones given below, which camps help to develop in children: confidence; creativity; talents
Answer:
(a) fun-filled and interesting.
(b) they impart lessons in yoga, cricket, tennis and swimming.
(c) productivity-oriented.
(d) The aim is the parent’s desire to tap the potential of their children to the fullest.
(e) ‘They’ refers to the summer camps.
(f) hyperactive and aggressive.
(g) independence
(h) mutual understanding

MP Board Class 11th Special English Unseen Passage 2

THE RABBITS WHO CAUSED ALL THE TROUBLES

1. Within the memory of the youngest child there was a family of rabbits who lived near a pack of wolves. The wolves announced that they did not like the way the rabbits were living. One night several wolves were killed in an earthquake and this was blamed on the rabbits, for it is well known that rabbits pound on the ground with their hind legs and cause earthquakes. On another night one of the wolves was killed by a bolt of lightning and this also was blamed on the rabbits, for it is well known that lettuce-eaters cause lightning.

2. The wolves threatened to civilise the rabbits if they did not behave, and the rabbits decided to run away to a desert island. But the other animals, who lived at a great distance, shamed them saying, “You must stay where you are and be brave. This is no world for escapists. If the wolves attack you, we will come to your aid, in all probability.” So the rabbits continued to live near the wolves. And one day there was a terrible flood which drowned a great many wolves. This was blamed on the rabbits, for it is well known that carrot nibblers with long ears cause floods. The wolves descended on the rabbits for their own good, and imprisoned them in a dark cave, for their own protection.

3. When nothing was heard about the rabbits for some weeks, the other animals demanded to know what had happened to them. The wolves replied that the rabbits had been eatem and since they had been eaten the affair was a purely internal matter. “They were trying to escape,” said the wolves, “and, as you know, this is no world for escapists.” Jamey Thurber

Question 1.
On the basis of your reading of the passage above, complete the following sentences. Write the answers in your answer sheet against the correct numbers.
(a) According to the wolves, the earthquake was caused by the rabbits, ……………………
(b) The rabbits did not run away from their place of living, to other safe place because ……………………
(c) Pick up two words from the passage which the wolves have used to indicate the nature of rabbits.
(d) What characteristic of the wolves does the phrase for their own good’ reveal?
(e) The wolves justified their action to the other animals by saying ……………………
(f) The final fate of the rabbits was ……………………
(g) ‘a purely Internal matter is humorous because ……………………
(h) The title ‘The Rabbits Who Caused All the Troubles’ is significant because ……………………
Answer:
(a) for it is well known that rabbits pound on the ground with their hind legs and cause earthquakes.
(b) they did not want to be shamed for being escapists.
(c) (i) lettuce-eaters (ii) carrot-nibblers
(d) This phrase reveals the self-centred nature of the wolves
(e) that the rabbits were trying to escape and this is no world for escapists
(f) imprisonment in a dark cave and being devoured by the wolves.
(g) the matter is not at all an internal one
(h) it is ironical as it was only the wolves who thought that the rabbits caused all the troubles

MP Board Class 11th Special English Unseen Passage 3

1. We’ve just left the dinner table, when I hear music coming from my daughter’s computer. It surprises me that my daughter Ida is listening to music from a time she refers to as the very old days. “What are you playing?” I ask. “It’s Phi Collins,” is her prompt reply, while she shows how, with a few strokes, she can download almost any song from the Internet. Times have certainly been changing since I scratched my first Beatles record. Tactfully I don’t mention that I had bought the record she’s listening to before she was bom. The concept of a phonograph record belongs to a bygone age and I don’t want to spoil the pleasure she’ll get from discovering her “own” new favorite musician.

2. The music brings memories flooding back. I have a sudden urge to bring back my record collection from the attic, where it has moldered for almost a decade. Only one thing stops me : my turntable succumbed to the damp air in a cellar where I stored it for a good ten years. No, I don’t care if turntables are ancient technology: I will find one. And I will restore my long lost record collection—-which took up a good amount of shelf space— to its former glory. Buying something as uncool as a turntable takes courage and planning. I find a promising TV and radio store in the phone book but I am expecting a mountain of Questions from the clerk, who will most certainly have been born and raised after the demise of the turntable.

3. “A turntable? Coming right up!” says the young man behind the counter. He disappears into the storeroom and before I can say long-playing record, he’s back with a small cardboard under his arm. It’s too good to be true. An hour later my new acquisition is in thej living room and a respectful atmosphere descends. I’ve sorted my records into piles all over the floor, I find a Beatles album.

4. Behind the wonderful music now flowing through the loudspeaker is the unmistakable sound of vinyl. It doesn’t take long for my twelve-year-old son’s eagle eye to spot the turntable and he has to try it out. Jonas is technically minded, a child of the computer age, yet I sense a certain reverence as he picks up the tone arm and tries to place it in the middle of the record. Brought up in the CD age how could he know what’s wrong? I say in a soothing voice: “The starting groove is on the edge of the record.” “Does it matter which side is up?” queried my daughter. “It does matter,” I replied. Soon we were listening to a Phil Collins number we both like. The generation gap vanishes as the music takes over. I relish the moment to the full and cast a glance at Ida. She’s relaxed and smiling. _

Question 1.
Fill in the following summary using only one word for each blank. Write the answers in your answer sheet against the correct blank number.
It was a moment of surprise for the author to (a) …………………… that his daughter had the same (b) …………………… for music as he had. This brought back (c) …………………… of his (d) …………………… collection in the attic. Though, a (e) …………………… task, he was (f) …………………… in locating a turntable.
Answer:
(a) discover (b) passion/interest (c) memories (d) record (e) difficult (f) successful

Question 2.
Complete the following sentences. Write the answers in your answer sheet.
(a) Jonas did not know how to handle the turntable as ……………………
(b) Music could bridge the generation gap as ……………………
(c) The author was reluctant to bring out his turntable from the cellar because ……………………
Answer:
(a) he was seeing it for the first time and he was, a technically minded computer age child.
(b) it takes over the complete atmosphere and makes one relish each moment to the full.
(c) it had moldered there for almost a decade and might have succumbed to the damp air in a cellar

Question 3.
Find words from the passage which mean the same as the following
(a) skillfully avoiding giving offense (para 1)
(b) a feeling of respect (para 4)
Answer:
(a) tactfully (b) reverence

MP Board Class 11th Special English Unseen Passage 4

1. Papaya is the healthiest fruit with a list of properties that is long and exhaustive. Belonging to the family of Caricaceae fruit, it is commonly kown as Papaw in Australia and Mamao in Brazil. It first originated in southern Mexico and neighbouring Central America, but is now available in every tropical and subtropical country. Papaya favours digestion as well as cures skin irritation and sun burns. You can munch on it as a salad, have it cooked or boiled or just drink it up as milkshake or juices. Modern science confirms the age-old beliefs that papaya has much to contribute to the health cause. The most important of these virtues is the protein-digesting enzyme in the milky juice or latex. The enzyme is similar to pepsin in its digestive action and is said to be so powerful that it can digest 200 times its own weight in protein. It assists the body in assimilating the maximum nutritional value from food to provide energy and body building materials.

2. Papain in raw papaya makes up for the deficiency of gastric juice and fights excess of, unhealthy mucus in the stomach, dyspepsia and intestinal irritation. The ripe fruit, if eaten regularly corrects habitual constipation, bleeding piles and chronic diar- ‘ rhoea. The juice of the papaya seeds also assists in the above- mentioned ailments.

3. The juice, used as a cosmetic, removes freckles or brown spots due to exposure to sunlight and makes the skin smooth7 and delicate. A paste of papaya sgeds is applied in skin diseases like those caused by ringworm. The black seeds of the papaya are highly beneficial in the treatment of cirrhosis of the liver caused by alcoholism, malnutrition, etc. A tablespoonful of its juice, combined with a hint of fresh lime juice, should be consumed once or twice daily for a month. The fresh juice of raw papaya mixed with honey can be applied over inflamed tonsils, for diphtheria and other throat disorders. It dissolves the membrane and prevents infection from spreading.

Question 1.
Complete the following :
(a) The other names for papaya are :
(b) Though now found in every tropical country
(c) One of the most important virtues of papaya is:
(d) Intestinal irritation can be overcome.
(e) Diseases cured by papaya are
(f) Throat disorders can be cured if
Answer:
(a) Papaw and Mamao.
(b) it first originated in Southern Mexico and neighboring Central America.
(c) the protein-digesting enzyme in the milky juice or latex.
(d) by the papain in raw-papaya.
(e) habitual constipation, bleeding piles and chronic diarrhea.
(f) fresh juice of raw papaya mixed with honey is applied over inflamed tonsils.

Question 2.
Complete the table below

Portion / extract Juice (b) ………………………………….. Black seeds

treatment for (a) ………………………………….. Skin diseases (d) …………………………………..

caused by Exposure to sunlight (c) ………………………………….. Alcoholism”

Answer:
(a) freckles or brown spots
(b) Paste of Papaya seeds
(c) ringworm
(d) cirrhosis of the liver

MP Board Class 11th Special English Unseen Passage 5

1. Set in the declining but still green Western Ghats in the south west of Karnataka, Coorg is the heart of India’s coffee country, coffee being the world’s most heavily traded commodity after crude Oil. Coorg boasts a land area four times larger than Hong Kong and seven times the area of Singapore, most of it is under tree cover because unlike tea plants, the coffee bush requires shade.

2. India is acknowledged as the producer of the finest mild coffees. j With their tropical climate, high altitude, abundant rainfall and fertile soil, Coorg and the neighbouring Chickmagalur districts in Karnataka have consistently produced and exported high-quality coffee for over 150 years. The coffee output of these I two districts accounts for 70 percent of the total coffee produced in the country. Coorg coffee is valued for its blue colour, clean beans and fine liquoring qualities and hence is in demand in the international markets.

3. In March and April is the coffee blossom time in Coorg. When blossom transform into berries, the bushes are cropped. The cherry-red fruit is then pulped; the seeds separated, dried and sent for curing, Coorg or Kodagu is the district which is one of the largest producers of pepper, cardamom and honey in the world.

4. Not rftuch is known about early history of Coorg. Recorded history is available only from 1600 AD onwards when Kodava \ rajas ruled over the region and established their capital at Mercara by constructing a mud walled fort. The martial Kodavas troubled Hyder Ali and his son Tipu Sultan who ruled the Mysore region in the 18th century by way of sporadic rebellions. But in 1785, Tipu’s large army marched into Kodagu and devastated the kingdom. Fourteen years later, with the help of the British who defeated Tipu Sultan following the historic siege of Srirangapatana ^ in 1799, Coorg regained independence and under the leadership of Raja Veerarajendra rebuilt the capital. Later in 1834, the British exiled its ruler Chikkaveera Rajendra and assumed administrative charge of the district. The British left India’ in 1947, leaving behind a legacy of coffee plantations, colonial buildings and well- planned road networks.

Question 1.
Complete the following:
(a) The tea plants are unlike coffee plants as the latter
(b) Coorg coffee is internationally acclaimed for its
(c) Coorg is famous not only for-coffee but also for
(d) After crude oil, coffee is the
Answer:
(a) require shade
(b) blue colour, clean beans and fine liquoring qualities
(c) pepper, cardamom and honey
(d) world’s most heavily traded commodity

Question 2.
Complete the table given below:

Year	Events
(a) ……………………………………………..	Recorded history of Coorg
1783 AD	available from
	(b) ……………………………………………..
(c) ……………………………………………..	Coorg regained independence
1834 AD	(d) ……………………………………………..

Answer:
(a) 1600 AD
(b) Tipu’s large army marched into Kodagu and .devastated the kingdom.
(c) 1799
(d) British exiled the ruler Chikkaveera Rajendra and assumed administrative charge of the district.

MP Board Class 11th Special English Unseen Passage 6

1. India Was once considered the land of knowledge and enlightenment. In ancient times scholars from all over Asia and Europe used to flock to Taxila, Nalanda and other Indian centres of learning. Apart from the arts, culture, philosophy and religion, these scholars came to study medicine, law and martial sciences. But despite having a vastly expanded university system and historical advantages, modern India has yet to provide international or even regional leadership in higher education. From the surrounding countries of Asia and Africa only a few students come to India for higher education.

2. The United States is by far the most successful country in attracting foreign students. But other countries such as Australia, Canada and Britain also aggressively market their universities abroad through their education counseling services and recruitment fairs with the active cooperation of their diplomatic missions abroad.

3. Likewise, India should also capitalise on the advantages offered by its higher education institutions, market Indian universities abroad and facilitate the entry of foreign students into them.

4. The revenue from foreign students can be used to ease the financial crunch faced by Indian universities, improve academic facilities and subsidise the cost of educating Indian students.

5. But apart from economic advantages many other benefits would accrue to the nation. India would gain global and regional influence, goodwill and become a major provider of higher education. Many Asian and African countries, especially the sinaller ones have poorly developed university systems and would look to Indian universities for the higher education of their youth. At the same time Indian students will not be deprived if 10 per cent supernumerary seats for foreign students are created in universities and professional colleges.

6. Already professional education in India has proved accessible and affordable for foreign students, especially from Malaysia, the Middle East and South Africa. In these countries higher education training facilities are limited. Many NRI (non-resident Indian) families abroad, especially those from English-speaking industrialised countries are also keen to send their children to study in their motherland and hopefully to become attuned to their Indian roots in the process.

Question 1.
On the basis of your reading of the passage complete the sentences given below. Write the answers in your answer sheet against the correct blank numbers. Do not copy the whole sentence.
(a) In spite of India having a historical advantage and a vastly expanded university system it ………………………
(b) Many parents send their children to India hoping that ………………………
(c) Academic facilities in India can be improved with ………………………
Answer:
(a) has yet to provide international or even regional leadership in higher education.
(b) by studying in their motherland these children would become attuned to their Indian roots.
(c) the revenue earned from the foreign students.

Question 2.
On the basis of yoq,r reading of the passage complete the following paragraph using one word only in each blank. Write the answers in your answer sheet against the correct blank numbers.

The income from foreign students would not only (a) …………………….. in educating Indian students but also in (b) ……………………… global and regional influence and thus (c) to higher education (d) The (e) ……………………… of countries with poorly developed education systems usually (f) ……………………… on Indian Universities for their higher education.
Answer:
(a) help (b) improving (c) provide (d) system (e) students (f) depend

Question 3.
Find words/phrases from the passage which mean the same as the following from the paragraphs indicated. _
(a) forceful (para 2) (b) easy to approach/to enter (para 5)
Answer:
(a) aggressive (b) accessible

MP Board Class 11th Special English Unseen Passage 7

1. Our house is filled with photos. They cover the walls of my kitchen, dining room and den. I see our family’s entire history, starting with my wedding, continuing through the births of both sons, buying a home, family gatherings and vacations. When my sons were little, they loved to pose. They waved, danced, climbed trees, batted balls, hung upside down’ from the jungle gym and did anything for a picture. But when they reached adolescence, picture-taking changed into something they barely tolerated. Their bodies were growing at haphazard speeds. Reluctantly they stood with us or with their grandparents at birthday celebrations and smiled weakly at the camera for as short a time as possible.

2. I am the chronicler of our photographs. I select those to be framed and arrange the others in albums. The process is addictive,. and as the shelves that hold our albums become fuller and fuller, I wonder what will become of them. Will anyone look at these photographs in future years? If my sons look at them, what will they think of us and of themselves? One bright afternoon, I took some photographs of my father with my husband as they fished on a lake near our vacation house. As my sons and I sat on the shore and watched them row away, I picked the camera up and photographed the beautiful lake surrounded by green trees. The two men I loved gradually grew smaller until all I could see were my father’s red shirt, and the tan and blue caps on their heads.

3. My father died a week later, and suddenly those photos became priceless to me. I wept when I pasted them in our album. I wept again after wards when I saw- my younger son looking at them. It was a few days before he went away to college. He had taken all our albums down from the bookshelves in the den and spread them out on the carpet. It had been A very long time since I had seen, him doing this. Once he stopped posing for pictures, he seemed to lose interest in looking at them. Bur now he was on the verge of leaving home. This was his special time to look ahead and look back. I stood for a moment in the hall by the den, and then tiptoed away. I didn’t take a photo of my son that afternoon, but I will remember how he looked for as long as I live. Some pictures, I learned, don’t have to be taken with a camera.

Question 1.
Fill in the summary using a word only:
The author was (a) …………………… about taking photographs and framing them. But she always (b) …………………… whether her sons would ever look at them. She was full of (c) …………………… when she pasted the pictures of her father’s last days in the album. She learned that some pictures always (d) …………………… in one’s mind without a camera.
Answer:
(a) addictive (b) wondered (c) tears (d) remained

Question 2.
Complete the sentences given below:
The author’s sons enjoyed getting photographed while they
(a) …………………… …………………… …………………… ……………………
(b) …………………… …………………… …………………… ……………………
(c) …………………… …………………… …………………… ……………………
(d) …………………… …………………… …………………… ……………………
Answer:
(a) waved and danced
(b) climbed trees
(c) batted balls
(d) hung upside down from the jungle gym

MP Board Class 11th Special English Unseen Passage 8

THE WORLD
Great, wide, beautiful, wonderful World,
With the wonderful water round you curled,
And the wonderful grass’ upon your breast—
World, you are beautifully drest.
The wonderful air is over me,
And the wonderful wind is shaking the tree,
It walks on the water, and whirls the mills,
And talks to itself on the tops of the hills.
You friendly Earth, how far do you go,
With the wheat-fields that nod and the rivers that flow!
With cities and gardens, and cliffs, and isles,
And people upon you for thousands of miles?
Ah! you are so great, and I am so small,
I tremble to think of you, World, at all;
And yet, when I said my prayers to-day,
A whisper inside me seemed to say,
‘You are more than the Earth, though you are such a dot:
You cam love and think, and the Earth cannot !’

—W.B. Rands

Question 1,
On the basis of your understanding of the poem above complete the following sentences. Write the answers in your answer sheet against the correct blank numbers.
(a) The T refers to the (1) …………………… and the ‘you’ refers to the (2) …………………… in the poem.
(b) Pick out and write any two words from the poem refer to the grandeur of the earth.
(c) Pick out and write the words from the poem that refer to the following
(1) The green dress of the earth ……………………
(2) Whisper of the wind ……………………
(3) Fear in the speaker ……………………
(4) Oceans surrounding the earth ……………………
(d) ‘You are more than the Earth, though you a such a dot’ because ……………………
Answer:
(a) (i) poet, (ii) earth,
(b) (i) great (ii), wonderful,
(c) (i) wheat fields, gardens (ii) And talks to itself on the top of the hills (iii) tremble to think of you. (iv) With the wonderful water round you curled, (d) the poet can love and think and the Earth cannot.

MP Board Class 11th Special English Unseen Passage 9

THE COROMANDEL FISHERS

Rise, brothers, rise; the wakening skies pray to the morning light,
The wind lies asleep in the arms of the dawn like a child that has cried all night.
Come, let us gather our nets from the shore and set our catamarans tree,
To capture the leaping wealth of the tide, for we are the kings -of the sea! ‘
No longer delay, let us hasten away in the track of the ‘seagull’s call,
The sea is our mother/ the cloud is our brother, the waves are our comrades all.
What though we toss at the fall of the sun where the hand of the sea-god drives?
He who holds the storm by the hair, will hide in his breast our lives.
Sweet is the shade of the cocoanut glade, and the scent of the mango grove,
And sweet are the sands at the full o’ the moon with the sound of the voices we love;
But sweeter, O brothers, the kiss of the spray and the dance of the wild foam’s glee;
Row, brothers, row to the edge of the verge, where the low sky -mates with the sea.

—Sarojini Naidu

Question 1.
On the basis of your understanding of the poem above, complete the following sentences. Write the answers in your answer sheet against the correct blank numbers.
(a) The poet refers to fishermen through different words. Two of them are : (i) …………………… (ii) ……………………
(b) The leaping wealth of the tide is (i) …………………… which the fishermen catch with their (ii) ……………………
(c) The Sea-God would (i) …………………… even if (ii) ……………………
(d) Pick out and write the word (s) from the poem that refers to :
(i) The coming of the morning ……………………
(ii) The wind is not wild ……………………
(iii) The sea waves are the fishermen’s friends ……………………
Answer:
(a) (i) brothers (ii) kings of the sea
(b) (i) fish (ii) nets
(c) (i) drive his hand (ii) they toss at the fall of the sun.
(d) (i) wakening skies (ii) the wind lies asleep (iii) the waves are our comrades all

MP Board Class 11th Special English Unseen Passage 10

A GREEN CORNFIELD

The earth was green, the sky was blue;
I saw and heard one sunny morn
A skylark hang between the two,
A singing speck above the corn.
A stage below in gay accord,
White butterflies danced on wing,
And still the singing skylark soared,
And silent sank and soared to sing.
The cornfield stretched a tender green
To right and left beside my walks;
I knew he had a nest unseen
Somewhere among the million stalks.
And as I paused to hear his song
While swift the sunny moments slid,
Perhaps his mate sat listening long,
And listened longer than I did.

Question 1.
Read the following summary. Complete it by writing the missing words against the correct blank number in your answer sheet.
The poet’s intense (a) ……………………. for nature is (b) ……………………. in the poem. She looked (c) ……………………. from a cornfield and saw a (d) ……………………. soaring in the sky and (e) ……………………. The butterflies (f) ……………………. about in the cornfield. The poet knew that the skylark’s (g) ……………………. was hidden (h) the stalks. She (i) ……………………. that its (j) ……………………. too was listening intently to the song.
Answer:
1. (a) love (b) evident (c) up (d) skylark (e) singing (f) danced (g) nest (h) among (i) thought (j) mate

Question 2.
Complete the following statements on the basis of your reading of the poem. Write your answers in the answer sheet 1 against the correct blank number:
(a) The colours mentioned in the poem are ……………………
(b) One sunny morning the poet ……………………
(c) The phrase ‘gay accord’ in the second stanza means ……………………
Answer:
(a) green and blue.
(b) saw a skylark soaring and singing in the blue sky above the green cornfield.
(c) The phrase ‘gay accord’ means “set in a happy and cheerful atmosphere”.

MP Board Class 11th Special English Unseen Passage 11

1. Why is it that there are very few women players in our orchestras? If one could reply flatly—sex discrimination: they don’t want women in orchestras—that would be a definite answer. But one can’t say that. As a matter of fact there are, if not many, a few women playing today in symphony orchestras. Nevertheless, it is true that male orchestral players are in an over whelming majority. Why is that? I’m afraid, there is no one answer. There are physical reasons why women don’t perform well on certain instruments. The average woman is not likely to possess sufficient lung power and sheer muscular strength to play the tuba just as an average woman’s hands are not likely to be large enough to finger a double bass satisfactorily. But what about the other instruments?

2. I think social and family pressures have been very strong in keeping women out of orchestras. Think of the prejudice that existed half a century ago against the so-called ‘nice’ girls going on-stage. The stage was won out for the simple reason that it had to have women to play feminine roles in plays and operas, and was willing to offer a young woman more money than she could make in any other profession. Moreover, on stage, she was appearing as an individual, as a center of attraction. This was gratifying to both her and her-family. To this day, while the average parents are reconciled to seeing their daughter become an opera singer or concert artist, they don’t like the idea of seeing her submerging her personality to become ‘the member of a chorus of the orchestra.

3. Another reason why we have so few women orchestral musicians is that so few of them play wind instruments well enough. They don’t play well enough because they haven’t had the proper training; and the reason for that lies in the history of orchestral music. You will find that famous European family of bassoon players or clarinetists taught their sons^ to play the family instrument. Their sons; but never their daughters. If they had any other pupils, those were also boys; not girls. And to this day, while women vote, hold public office and practise many other professions, without shocking our sensibilities, in this particular field, the orchestra, our attitude towards women still remains the same. However, this prejudice is rapidly crumbling, 7 and is likely to disappear entirely in a few years. For this we7 have to thank our high-school bands and orchestras, which offer/ instruction, practice and experience in playing all orchestral/instruments to boys and girls alike.

Question 1.
Complete the following sentences. Write the answers in your answer sheet against the correct blank number;
I. The reason why there are only very few women orchestra players—
(a) Physical reasons
(i) ………………………
(ii) ………………………

(b) Social reasons
(i) ………………………
(ii) ………………………

(c) Women won out on stage because
(i) ………………………
(ii) ………………………

II. The high school bands have to be thanked because
III. Lack of training has resulted in …..
Answer:
1. (a) (i) lack of sufficient lung power and sheer muscular strength to play the tuba
(ii) average woman’s hands are not large enough to finger a double bass satisfactorily (i) family pressure strong in keeping women out of orchestras.

(ii) prejudice exists, against girls going on stage.
(i) it had to have given to play feminine roles in plays and operas, (ii) offered a young woman more money that she could make in any other profession.
II. they offer instruction, practice and experience in playing all orchestral instruments to boys and girls alike.
III. having very few women orchestral musicians.

Question 2.
Find words from the passage which mean the same as the phrases given below. Write your answers in the answer sheet
Answer:
(a) discrimination, (b) crumbling, (c) gratifying, (d) training

MP Board Class 11th Special English Unseen Passage 12

1. We’ve just left the dinner table, when I hear music coming from my daughter’s computer. It surprises me that my daughter Ida is listening to music from a time she refers to as the very old days. “What are you playing?” I ask. “It’s Phil Collins,” is her prompt reply, while she shows how, with a few strokes, she can download almost any song from the Internet. Times have certainly been changing since I scratched my first Beatles record. Tactfully I don’t mentiop that I had bought the record she’s listening to before she was born. The concept of a phonograph … record belongs to a bygone age and I don’t want to spoil the pleasure she’ll get from discovering her “own” new favourite musician.

2. The music brings memories flooding back. I have a sudden urge to bring back my record collection from the attic, wngre it has mouldered for almost a decade. Only one thing stops me : my turntable succumbed to the damp air in a cellar where I stored. it for a good ten years. No, I don’t care if turntables are ancient technology: I will find one. And I will restore my long lost record collection—which took up a good amount of shelf space— to its former glory. Buying something as uncool as a turntable takes courage and planning. I find a promising TV and radio store in the phone book but I am expecting a mountain of Question s from the clerk, who will most certainly have been born and raised after the demise of the turntable.

3. “A turntable? Coming right up.'” says the young man behind . the counter. He disappers into the storeroom and before I can say long-playing record, he’s back with a small ‘cardboard under his arm. It’s too good to be true. An hour later my new acquisition . is in the living room and a respectful atmosphere descends. I’ve sorted my records into piles all over the floor, I find a Beatles album.

4. Behind the wonderful music now flowing through the loud speaker is the unmistakable sound of vinyl. It doesn’t take long for my twelve year old son’s eagle eye to spot the turntable and he has to try it out. Jonas is technically minded., a child of the’xromputer age, yet I sense a certain reverence as he picks up the tone arm and tries to place it in the middle of the record. Brought up in the CD age how could he know what’s wrong?

I say in a soothing voice: “The starting groove is on the edge of the record.” “Does it matter which side is up?” queried my daughter. “It does matter,” I replied. Soon we were listening to a Phil Collins number we both like. The generation gap vanishes as the music takes over. I relish the moment to the full and cast a glance at Ida. She’s relaxed and smiling.

Question 1.
Fill in the following summary using only one word for each blank. Write the answers in your answer, sheet against the correct blank number.
It was a moment of surprise for the author to (a) ……………………… that his daughter had the same (b) ……………………… for music as he had. This brought back (c) ……………………… of his (d) ……………………… collection in the attic. Though, a (e) ……………………… task, he was (f) ……………………… in locating a turntable.
Answer:
(a) discover (b) passion/interest (c) memories (d) record (e) difficult (f) successful

Question 2.
Complete the following sentences. Write the answers in your answer sheet.
(a) Jonas did not know how to handle the turntable as
(b) Music could bridge the generation gap as
(c) The author was reluctant to bring out his turntable from the cellar because
Answer:
(a) he was seeing it for the first time and he was a technically minded computer age child.
(b) it takes over the complete atmosphere and makes one relish each moment to the full.
(c) it had moldered there for almost a decade and might have succumbed to the damp air in a cellar.

Question 3.
Find words from the passage which mean the same as the following.
(a) skillfully avoiding giving offense (para 1)
(b) a feeling of respect (para 4)
Answer:
(a) tactfully (b) reverence

MP Board Class 11th Special English Unseen Passage 13

NIGHT

The Sun descending in the west,
The evening star does shine;
‘The birds are silent in their nest,
And I must seek for mine.
The Moon, like a flower,
In heaven’s high bower,
With silent delight
Sits and smiles on the night.
Farewell, green fields and happy groves,
Where lambs have nibbled, silent moves
The feet of angels bright;
Unseen they pour blessing,
And joy without ceasing,
On each bud and blossom,
And each sleeping bosom.
“They look in every thoughtless nest,
Where birds are covered warm;
They visit caves of every beast,
To keep them all from harm.”
If they see any weeping
That should have been sleeping
They pour sleep on their head/
I And sit down by their bed.

—William Blake

Question 1.
Below is a summary of the poem. Complete it by writing the missing word/phrase against the correct blank number in your answer sheet.
K This poem conveys a beautiful impression of pe&ce and quietness that falls over the landscape at (a) ……………………………. At this time there is (b) ……………………………. everywhere. The poet compares the moon to a (c) ……………………………. It appears to be silently sitting and (d) ……………………………. during the night. The poem conveys a feeling of trust in God’s protection. His (e) ……………………………. angels whose feet are bright, shower (f) ……………………………. of safe sleep on all.
Answer:
(a) night (b) silence (c) flower (d) smiling (e) unseen (f) blessings

Question 2.
What do the angels do to the following, when they visit them at night? Write the answers in your answer sheet against the correct blank numbers.
(a) birds in their nests
(b) beasts in their caves
(c) any weeping creature
Answer:
(a) to look at the warmly covered birds.
(b) to ensure that they are free from harm.
(c) to make sure that they sleep by pouring sleep on its head.

Question 3.
Find words/phrases from the poem which means the same as the following.
(a) areas of land with fruit trees of a particular type
(b) took small bites of food
Answer:
(a) groves, (b) nibbled.

MP Board Class 11th Special English Unseen Passage 14

1. Although everybody has a creative spark, the potential not always fully utilised. How does one recognise those who are developing their creative energies to the fullest? Mad painters and tormented poets are only comic stereotypes of the creative personality. The essential traits of creativity are found among ” a wide variety of less conspicuous creators, people in all walks of life. Unfortunately, the structure of our social and educational environment does not always promote its growth.

2. Generally speaking, creative people often believe their purpose in life is to discover and implement the interrelatedness of things, to make order out of disorder. They also see problems where others see none and Question the validity of even the most widely accepted answers. Creative persons are compulsive problem seekers, not so much because they thrive on problems, but because their senses are attuned to a world that demands to be put together, like a jigsaw puzzle scattered on a table.

3. Several tests now in use reveal that highly creative people are much more open and receptive to the complexities of experience than are less creative people. The creative temperament has a tendency to break problems down into their most basic elements, and then reconstruct them into whole new problems, thereby discovering new relationships and new solutions.

4. Highly creative people aren’t afraid to ask what may seem to be naive or silly Question s. They ask questions like, “why don’t spiders get tangled up in their own webs?” and, “why do dogs turn in circles before lying down?”., Such Questions s may seem childlike, and in a way they are. Children have not yet had their innate creative energies channeled into culturally acceptable directions and can give full rein to their cariosity —the absolute prerequisite for full’ creative functioning, both children and adults. ‘

5. Unlike children, creative people appear to have vast stores of patience to draw upon. Months, years, even decades can be devoted to a single problem.

6. The home that encourages inquisitiveness contributes to creative development. The teacher who stresses Question s rather than answers and rewards curiosity rather than restricting it is teaching a child to be creative.

7. To be extremely intelligent is not the same as to be gifted in creative work. The Quiz Kids are often referred to as geniuses. They would undoubtedly score high in memory functions …. But it is doubtful whether they are also fluent in producing ideas.

8. Contrary to popular myths that glorify youth, more creative achievements are likely to occur when people grow older. While memory may falter with age, creativity is ageless. (425 words)

Question 1.
On the basis of your reading of the passage above, complete the following sentences:
Write the answers in your answer sheets against the correct blank number.
(a) Every person is not able to use his/her creativity fully because of the ……………………… .
(b) Three traits of highly creative people, that we get to know from the passage are :
(i) ………………………
(ii) ………………………
(iii) ………………………
(c) The most essential prerequisite for full creative functioning ………………………
(d) The Quiz’ Kids may be great in (i) ……………………… but they cannot be called creative unless they can (ii) ………………………
(e) Teachers can promote creativity among students by ………………………
(f) Growing older does not affect creativity.
Pick out and write the words/phrase from the passage in support of this view:
……………………………………………………………………………………………….
Answer:
(a) structure of our social and educational environment which does not always promote their creative growth.
(b) (i) They believe their purpose in life is to discover and implement ’ the interrelatedness of things.
(ii) They make order out of disorder.
(iii) The Question the validity of even the most widely accepted answers of problems.
(c) not to be afraid to ask what may seem to be naive or silly Question s.
(d) (i) memory function (ii) produce fluent ideas
(e) rewarding curiosity rather than restricting it.
(f) creativity is ageless.

Question 2.
Find words/phrases from the passage which mean the same as the following, from the paragraph indicated. Write the answers in your answer sheets against the correct blank number.
(i) noticeable (para 1)
(ii) natural and instinctive (para 4)
(iii) simple and innocent (para 4)
(iv) commonly held notions (para 8)
Answer:
(i) conspicuous (ii) innate (iii) naive (iv) myths

MP Board Class 11th Special English Unseen Passage 15

WHICH LOVED BEST?

“I love you, Mother,” said little John;
Then, forgetting his work, his cap went on,
And he was off to the garden swing,
And left her the water and wood to bring.
“I love you, Mother,” said rosy Nell-
“I love you better than tongue can tell”;
Then she teased and pouted full half the day,
Till her mother rejoiced when she went to play.
“I love you. Mother,” said little Fan;
“Today I’ll help you all I can;
How glad I am that school doesn’t keep!”
So she rocked the babe till it fell asleep.
Then, stepping softly, she fetched the broom,
And swept the floor and tidied the room;
Busy and happy all day was she,
Helpful and happy as child could be.
“I love you. Mother,” again they said,
Three little children going to bed;
How do you think that mother guessed
Which of them really loved her best?

—Joy Allison

Question 1.
(a) Instead of helping his mother John
(b) John could have helped his mother by …………………………
(c) The mother rejoiced when Nell went to play because …………………………
(d) It was easy for Fan to help her mother because …………………………
(e) Fan kept herself busy and happy that day by and …………………………
(f) Fan? stepped softly into the room because she …………………………
(g) Mother guessed that Fan loved her most because her other two children …………………………
Answer:
(a) went off to the garden swing.
(b) bringing to her the water and the wood.
(c) she was irritating her mother by teasing and pouting at her.
(d) she did not have to go to school that day.
(e) sweeping the floor, tidying the room.
(f) did not want to disturb the sleeping baby.
(g) did not even bother to help her in her daily chores.

MP Board Class 11th Special English Unseen Passage 16

WHICH LOVED BEST?

1. Martin Luther King, one of the greatest men ever to walk on this earth, started the defence force with which the American Blacks got their rights and gained freedom from the distressing racial discrimination.

2; Martin was bom on January 15, 1929. His family lived on the outskirts of Atlanta. The fact that he could not play with White children, or that he had to offer a seat in the bus to a White, disturbed him. When he was eight years old, his father a Baptist pastor, told the family a sad story: Bessie Smith, a great singer, met with an ; accident. An ambulance rushed her to the nearest hospital, but she was not admitted because she was a Black. The ambulance took her from one hospital to another, but she could not find a place for herself because these hospitals were only for the Whites. She died for want of blood. From that day, Martin Luther King dreamt of becoming a liberator of the Blacks.

3. King completed his studies at More House College, and then earned a doctor’s degree in theology at Boston University. In 1955, King married Alabama Soprano, Coretta Scott. That very year he became a pastor and preached his first sermon in the Baptist Church of Atlanta. As a young man, he was greatly impressed by Mahatma Gandhi’s success in the political field and the power of ahimsa. King decided to follow the path of non-violence and get millions of Blacks their due. He felt that the Blacks had immensely contributed towards the building of America, and there was no reason why they should not be treated with respect.

4. King drew national attention in 1956. Since the Blacks were not permitted to sit in the same buses as the Whites, he led a boycott of public buses in Montgomery. A year later, after many arrests and threats, the US Supreme Court gave a ruling that racial segregation of public transport was unlawful. This victory taught the Blacks the power of non-violence. After 1957, King began visiting various places to deliver lectures. Soon he became a powerful orator, drawing the attention of people the world over.

5. King continued the fight, a peaceful fight, demanding the rights of the Blacks. In 1964, he was awarded the Nobel Peace Prize. In 1967, King led many peaceful demonstrations against the Vietnam War and in 1968 he declared a Poor People’s Campaign. On April 4, of that very year, while planning a demonstration of striking sanitation workers, he was shot dead by an assassin. (421 words)

Question 1.
On the basis of your reading of the above passage, complete the following sentences. Write the answers in your answer sheet against the correct blank number.
(a) Martin Luther King was disturbed by the fact that
(b) The story of motivated him to fight for the rights of the Blacks.
(c) He followed the path of non-violence because
Answer:
(a) he could not play with White children or that he had to offer a seat on the bus to a white.
(b) Bessie Smith, a great singer
(c) he was greatly impressed by Mahatma Gandhi’s success in the political field and the power of ‘ahimsa’.

Question 2.
Fill in the blanks to complete the following table. Write the answers in the answer sheet against the correct blank number.

Answer:
(a) 1955
(b) He drew national attention.
(c) He was awarded the Nobel Peace Prize.
(d) He led many peaceful demonstrations against the Vietnam War.
(e) 1968

Question 3. Find words from the passage which mean the same as the following from the paragraphs indicated. Write the answer in the answer sheet against the correct blank number.
(a) causing anxiety and pain (Para 1)
(b) very largely (Para 3)
(c) separation (Para 4)
(d) a person who murders (Para 5)
Answer:
(a) distressing iff) immensely (c) segregation (d) assassin

MP Board Class 11th Special English Unseen Passage 17

WHICH LOVED BEST?

1. Last June, my elder daughter Sylvie, finished kindergarten at the school near our home in Bethlehem, USA. If my wife, Theresa, and have our way, Sylvie will graduate from the same school. I aip eyeing Sylvie’s graduation because I want this to be her only school add Bethlehem to be her hometown. Both goals— first one a school, the second a hometown—eluded me. My father was in the army, and I attended numerous schools. Our transient lifestyle offered a grand upbringing, but it came at a cost. Of all those people I befriended on the run, for instance, I’ve maintained contact with exactly one. I’m generally from everywhere and exactly from nowhere.

2. I want Sylvie and her two-year-old sister Linnea, to have that hometown that I missed. It would be a place they know intimately, care about, return to with a thrill. So when Theresa took a teaching post in Bethlehem, we moved from Chicago and decided to settle down, here. That was almost six years ago, and the transition was rough. We did not like the paucity of movie houses, used-book stores and great restaurants. We found instead, cheap shopping malls; and cornfields being transformed into faceless suburbs. It was hard to imagine blossoming in such a place. We began to seek out the good things in Bethlehem, of which, we discovered, there are many. In short order we turned up the children’s comer of the public library, a number of parks and the folk-music dub that draws top performers to a venue no bigger than our living room.

3. Where we found good places, we found good people. Slowly their numbers increased. Soon we discovered we had knit together a circle of dear friends. As our friendship strengthened, so, too did an unspoken belief that we would be here for each other over the long haul. We’d watch each other’s children grow up; offer them a hand where we could, support each other through the joys and travails of parenthood.

4. There’s yearly party, a joint sale and more potluck dinners than I can count. We’ve celebrated both of Linnea’s birthdays with a bash on our front lawn. On Saturday mornings when many of us converge downtown, the shopkeepers greet me and my children by name, and hand out goodies. To the old-timers here, all this might be unremarkable. But to be the vagabond like me, this acceptance is heart-warming, nourishing and ultimately sustaining. So why resist its pull? Because it’s a mistake to take for granted a good community, or to assume we’d be lucky enough to find one somewhere else. In the end, good and lasting community arises from a commitment to it. And there’s no more basic commitment than staying put.

Question 1.
Complete the summary given below. Use only a word to fill in the blanks.
The author decided to stay put at Bethlehem’ as he wanted it to be his (a) ……………………….. hometown.

Though upset about the lack of (b) ……………………….. he and his wife started to seek out the good things there. Soon a strong bond developed between them and their (c) ……………………….. He resisted his (d) ……………………….. to move to greener pastures. He also (e) ……………………….. that only with commitment can a lasting community arise.
Answer:
(a) permanent (b) amenities (c) friends (d) temptation (e) realized

Question 2.
Find words which mean the same as the following:
(a) many/in large numbers (para 1)
(b) change (para 2)
(c) sorrows/unpleasant experiences (para 3)
(d) a person who travels from place to place (para 4)
Answer:
(a) of his transient lifestyle he was always on the run.
(b) out of all those people he befriended on the run.
(c) from a commitment to it.

Question 3.
Complete the following sentences:
(a) The author could not refer to any place as his hometown because
(b) The author had contact with only one friend
(c) The realization that lasting community arises
Answer:
(a) numerous (b) transition (c) travails (d) vagabond

MP Board Class 11th English Solutions

MP Board Class 12th Physics Solutions Chapter 8 वैद्युत चुम्बकीय तरंगें

वैद्युत चुम्बकीय तरंगें NCERT पाठ्यपुस्तक के अध्याय में पाठ्यनिहित प्रश्न एवं उनके उत्तर

प्रश्न: 1.
चित्र 8.1 में एक संधारित्र दर्शाया गया है जो 12 सेमी त्रिज्या की दो वृत्ताकार प्लेटों को 5.0 सेमी की दूरी पर रखकर बनाया गया है। संधारित्र को एक बाह्य स्त्रोत (जो चित्र में नहीं दर्शाया गया है) द्वारा आवेशित किया जा रहा है। आवेशकारी धारा नियत है और इसका मान 0.15 ऐम्पियर है।
(a) धारिता एवं प्लेटों के बीच विभवान्तर परिवर्तन की दर का परिकलन कीजिए।
(b) प्लेटों के बीच विस्थापन धारा ज्ञात कीजिए।
(c) क्या किरचॉफ का प्रथम नियम संधारित्र की प्रत्येक प्लेट पर लागू होता है? स्पष्ट कीजिए।

हल :
दिया है : प्लेट की त्रिज्या r = 0.12 मीटर, बीच की दूरी d = 0.05 मीटर
आवेशन धारा i= 0.15 ऐम्पियर
(a) संधारित्र की धारिता \(C=\frac{\varepsilon_{0} A}{d}\)
[∵ A =πr² = 3.14 × (0.12)²]
\(=\frac{8.854 \times 10^{-12} \times 3.14 \times(0.12)^{2}}{0.05}\)
= 8.01 × 10^-12F= 8.01 pF.
किसी क्षण संधारित्र पर आवेश q= CV ⇒ V=\(\frac { q }{ C }\)
∴\(\frac{d V}{d t}=\frac{1}{C} \frac{d q}{d t}=\frac{1}{C} i\)    ( ∵ \(\frac{d q}{d t}=i\) )
∴ विभवान्तर परिवर्तन की दर \(\frac{d V}{d t}=\frac{0.15}{8.01 \times 10^{-12}}\)
= 1.87 × 10¹⁰ वोल्ट सेकण्ड^-1.

(b). प्लेटों पर विस्थापन धारा \(i_{D}=\varepsilon_{0} \frac{d \phi_{E}}{d t}\)
जहाँ कै Φ_E प्लेटों के बीच स्थित किसी बन्द लूप से गुजरने वाला वैद्युत फ्लक्स है।
∵ प्लेटों के बीच वैद्युत क्षेत्र \(E=\frac{q}{\varepsilon_{0} A}\)
∴ यदि लूप का क्षेत्रफल A है तो

(c) हाँ, किरचॉफ का प्रथम नियम संधारित्र की प्रत्येक प्लेट पर भी लागू होता है क्योंकि
प्लेट तक आने वाली चालन धारा = प्लेट से आगे जाने वाली विस्थापन धारा

प्रश्न 2.
एक समान्तर प्लेट संधारित्र (चित्र 8.2), R = 6.0 सेमी त्रिज्या की दो वृत्ताकार प्लेटों से बना है और इसकी धारिता C = 100 pF है। संधारित्र को 230 वोल्ट, 300 रेडियन सेकण्ड^-1 की (कोणीय) आवृत्ति के किसी स्त्रोत से जोड़ा गया है।
(a) चालन धारा का r.m.s. मान क्या है?
(b) क्या चालन धारा विस्थापन धारा के बराबर है?
(c) प्लेटों के बीच, अक्ष से 3.0 सेमी की दूरी पर स्थित बिन्दु पर B का आयाम ज्ञात कीजिए।

हल :
दिया है : V_rms = 230 वोल्ट, ω = 300 रेडियन सेकण्ड^-1, C = 100 × 10^-12F. ..
त्रिज्या R = 0.06 मीटर
(a) चालनं धारा का rms मान \(i_{r m s}=\frac{V_{r m s}}{1 / \omega C}=V_{r m s} \omega C\)
= 230 × 300 × 100 × 10^-12
= 6.9 × 10^-6 ऐम्पियर
= 6.9 माइक्रोऐम्पियर।
(b) हाँ, संधारित्र के लिए सदैव ही चालन धारा विस्थापन धारा के बराबर होती है, भले ही धारा दिष्ट हो अथवा प्रत्यावर्ती।
(c) प्लेटों के बीच r= 0.03 मीटर त्रिज्या के बन्द लूप पर विचार कीजिए जिसका तल प्लेटों के तल के समान्तर है। इस लूप के प्रत्येक बिन्दु पर चुम्बकीय क्षेत्र B का परिमाण समान तथा दिशा स्पर्शरेखीय होगी जबकि वैद्युत क्षेत्र E लूप के तल के प्रत्येक बिन्दु पर समान तथा इसकी दिशा लूप के तल के लम्बवत् होगी।

प्रश्न 3.
10^-10 मीटर तरंगदैर्घ्य की x-किरणों, 6800 A तरंगदैर्घ्य के प्रकाश तथा 500 मीटर की रेडियो तरंगों के लिए किस भौतिक राशि का मान समान है?
हल :
उक्त तीनों प्रकार की तरंगों की तरंगदैर्घ्य तथा आवृत्तियाँ भिन्न-भिन्न हैं परन्तु ये सभी वैद्युतचुम्बकीय तरंगें हैं, अत: इन सबकी निर्वात में चाल (c = 3 x 10⁸ मीटर सेकण्ड^-1) समान है। .

प्रश्न 4.
एक समतल वैद्युतचुम्बकीय तरंग निर्वात में Z-अक्ष के अनुदिश चल रही है। इसके वैद्युत तथा चुम्बकीय क्षेत्रों के सदिश की दिशा के बारे में आप क्या कहेंगे? यदि तरंग की आवृत्ति 30 मेगाहर्ट्स हो तो उसकी तरंगदैर्घ्य कितनी होगी?
हल :
वैद्यत तथा चुम्बकीय क्षेत्रों के सदिशों की दिशाएँ तरंग संचरण की दिशा (Z-अक्ष) के लम्बवत् अर्थात् :समतल के समान्तर होंगी तथा परस्पर भी लम्बवत् होंगी। ::
∵ आवृत्ति υ = 30 × 10⁶ हर्ट्स
तथा चाल c = 3 × 10⁸ मीटर सेकण्ड^-1
∴ तरंगदैर्घ्य \(\lambda=\frac{c}{v}=\frac{3 \times 10^{8}}{30 \times 10^{6}}\) = 10 मीटर।

प्रश्न 5.
एक रेडियो 7.5 मेगाहर्ट्स से 12 मेगाहर्ट्स बैण्ड के किसी स्टेशन से समस्वरित हो सकता है। संगत तरंदैर्घ्य बैण्ड क्या होगा?
हल :
दिया है, आवृत्ति बैण्ड υ₁ = 7.5 × 10⁶ हर्ट्स से υ₂ = 12 × 10⁶ हर्ट्स ।
चाल c = 3 × 10₈ मीटर सेकण्ड_-1
∴ \(\lambda_{1}=\frac{c}{v_{1}}=\frac{3 \times 10^{8}}{7.5 \times 10^{6}}\) = 40 मीटर
तथा \(\lambda_{2}=\frac{c}{v_{2}}=\frac{3 \times 10^{8}}{12 \times 10^{6}}\) = 25 मीटर
∴ संगत तरंगदैर्घ्य बैण्ड 25 मीटर – 40 मीटर होगा।

प्रश्न 6.
एक आवेशित कण अपनी माध्य साम्यावस्था के दोनों ओर 10⁹ हर्ट्स आवृत्ति से दोलन करता है। दोलक द्वारा जनित वैद्युतचुम्बकीय तरंगों की आवृत्ति कितनी है?
हल :
हम जानते हैं कि त्वरित अथवा कम्पित आवेशित कण कम्पित वैद्युत क्षेत्र उत्पन्न करता है। यह वैद्युत क्षेत्र, कम्पित चुम्बकीय क्षेत्र उत्पन्न करता है। ये दोनों क्षेत्र मिलकर वैद्युतचुम्बकीय तरंग उत्पन्न करते हैं; जिसकी आवृत्ति, कम्पित कण के दोलनों की आवृत्ति के बराबर होती है। ..
∴ तरंगों की आवृत्ति υ = 10⁹ हौ।

प्रश्न 7.
निर्वात में एक आवर्त वैद्युतचुम्बकीय तरंग के चुम्बकीय क्षेत्र वाले भाग का आयाम B₀ = 510 नैनो टेस्ला है। तरंग के वैद्युत क्षेत्र वाले भाग का आयाम क्या है?
हल :
निर्वात में, B₀ = 510 नैनोटेस्ला ।
= 510 × 10^-9 टेस्ला
यदि निर्वात में वैद्युत क्षेत्र वाले भाग का आयाम = E_o
तब \(c=\frac{E_{0}}{B_{0}}\) ⇒ E_o = cB_o
E_o = 3 × 108 × 510 × 10^-9
= 153 वोल्ट मीटर^-1।

प्रश्न 8.
कल्पना कीजिए कि एक वैद्युतचुम्बकीय तरंग के वैद्युत क्षेत्र का आयाम E₀ = 120 न्यूटन/कूलॉम है तथा इसकी आवृत्ति υ = 50.0 मेगाहर्ट्स है। (a) B_o , ω , k तथा λ ज्ञात कीजिए, (b) E तथा B के लिए व्यंजक प्राप्त कीजिए। .
हल :
दिया है : E₀ = 120 न्यूटन कूलॉम^-1,
υ = 50.0 × 10⁶ हर्ट्स .
तरंग वेग c= 3 × 10⁸ मीटर सेकण्ड^-1
(a) सूत्र \(c=\frac{E_{0}}{B_{0}}\) से,
\(B_{0}=\frac{E_{0}}{c}=\frac{120}{3 \times 10^{8}}\) = 4.0 × 10^-7 टेस्ला
= 400 नैनोटेस्ला ।
ω = 2 πυ = 2 × 3.14 × 50 × 10⁶
= 3.14 × 10⁸ रेडियन सेकण्ड^-1
E_ok= B_o ω से,
\(k=\frac{B_{0} \omega}{E_{0}}=\frac{400 \times 10^{-9} \times 3.14 \times 10^{8}}{120}\)
= 1.05 रेडियन मीटर^-1।
\(\lambda=\frac{c}{v}=\frac{3 \times 10^{8}}{50 \times 10^{6}}\)= 6 मीटर।

(b) माना तरंग X-अक्ष की दिशा में गतिशील है, तब वैद्युत क्षेत्र तथा चुम्बकीय क्षेत्र क्रमश: Y. तथा Z-अक्ष की दिशाओं में माने जा सकते हैं।

प्रश्न 9.
वैद्युतचुम्बकीय स्पेक्ट्रम के विभिन्न भागों की पारिभाषिकी पाठ्यपुस्तक में दी गई है। सूत्र E = hυ (विकिरण के एक क्वांटम की ऊर्जा के लिए : फोटॉन) का उपयोग कीजिए तथा em (वैद्युतचुम्बकीय) वर्णक्रम (वैद्युतचुम्बकीय स्पेक्ट्रम) के विभिन्न भागों के लिए इलेक्ट्रॉन वोल्ट (ev) के मात्रक में फोटॉन की ऊर्जा निकालिए। फोटॉन ऊर्जा के जो विभिन्न परिमाण आप पाते हैं वे वैद्युतचुम्बकीय विकिरण के स्रोतों से किस प्रकार सम्बन्धित हैं?
हल :
सूत्र E = hυ जूल = \(\frac{h c}{\lambda}\) जूल = \(\frac{h c}{e \lambda} \mathrm{e} \mathrm{V}\)
∵ h = 6.62 × 10^-34 जूल सेकण्ड^-1, c= 3 × 10⁸ मीटर सेकण्ड^-1
e = 1.6 × 10^-19C
∴ \(E=\frac{6.62 \times 10^{-34} \times 3 \times 10^{8}}{1.6 \times 10^{-19} \times \lambda}=\frac{12.41 \times 10^{-7}}{\lambda}\) इलेक्ट्रॉन वोल्ट (ev)

(1) γ-किरणें-इन किरणों का माध्य तरंगदैर्घ्य 10^-12 मीटर है। अत:
\(E_{1}=\frac{12.41 \times 10^{-7}}{10^{-12}}=1.24 \times 10^{6} \mathrm{eV}\)
≈ 10⁶ इलेक्ट्रॉन वोल्ट।
अत: γ -किरणों की माध्य ऊर्जा 10⁶ इलेक्ट्रॉन वोल्ट होती है।

(2) x-किरणें-इनकी माध्य तरंगदैर्घ्य 10^-9 मीटर है।
∴ \(E=\frac{12.41 \times 10^{-7}}{10^{-9}} \approx 10^{3} \text { setagity alteel }\)
≈ 10 इलेक्ट्रॉन वोल्ट।
इनकी माध्य ऊर्जा 10³ इलेक्ट्रॉन वोल्ट होती है।

(3) पराबैंगनी विकिरण–इनकी माध्य तरंगदैर्घ्य 10^-8 मीटर होती है।
∴ \(E=\frac{12.41 \times 10^{-7}}{10^{-8}}=1.24 \times 10^{2} \mathrm{eV}\)
≈10² इलेक्ट्रॉन वोल्ट।

(4) दृश्य-प्रकाश–इनकी माध्य तरंगदैर्ध्य 10^-6 मीटर होती है।
∴ \(E=\frac{12.41 \times 10^{-7}}{10^{-6}}\)
= 1.24 इलेक्ट्रॉन वोल्ट।

(5) सूक्ष्म तरंगें-इनकी माध्य तरंगदैर्ध्य 10^-2 मीटर है जिसके लिए .
\(E=\frac{12.41 \times 10^{-7}}{10^{-2}}\)
= 1.24 × 10^-4 इलेक्ट्रॉन वोल्ट।

(6) रेडियो तरंगें—इनकी माध्य तरंगदैर्घ्य 10³ मीटर है। .
∴ \(E=\frac{12.41 \times 10^{-7}}{10^{3}}\)
= 1.24 × 10^-9 इलेक्ट्रॉन वोल्ट।

उक्त ऊर्जा परिणामों से स्पष्ट होता है कि γ-किरणें नाभिक के संक्रमण से निकलती हैं, X-किरणें पराबैंगनी विकिरण तथा दृश्य प्रकाश परमाणुओं के संक्रमण के कारण उत्सर्जित होते हैं।

प्रश्न 10.
एक समतल em (वैद्युतचुम्बकीय) तरंग में वैद्युत क्षेत्र, 2.0 × 10¹⁰ हर्ट्स आवृत्ति तथा 48 वोल्ट मीटर^-1 आयाम से ज्या वक्रीय रूप से दोलन करता है।
(a) तरंग की तरंगदैर्घ्य कितनी है?
(b) दोलनशील चुम्बकीय क्षेत्र का आयाम क्या है?
(c) यह दर्शाइए कि \(\overrightarrow{\mathbf{E}}\) क्षेत्र का औसत ऊर्जा घनत्व, \(\overrightarrow{\mathbf{B}}\) क्षेत्र के औसत ऊर्जा घनत्व के बराबर है। [c= 3 × 10⁸ मीटर सेकण्ड^-1]
हल :
दिया है : E₀ = 48 वोल्ट मीटर^-1, वैद्युत क्षेत्र की आवृत्ति = 2.0 × 10¹⁰ हर्ट्स
(a) ∵ तरंग की आवृत्ति υ = वैद्युत क्षेत्र की आवृत्ति = 2 × 10¹⁰ हर्ट्स
∴ तरंग की तरंगदैर्घ्य \(\lambda=\frac{c}{v}=\frac{3 \times 10^{8}}{2 \times 10^{10}}\)
= 1.5 × 10^-2 मीटर।

(b) \(c=\frac{E_{0}}{B_{0}}\) से, चुम्बकीय क्षेत्र का आयाम \(B_{0}=\frac{E_{0}}{c}=\frac{48}{3 \times 10^{8}}\)
= 1.6 × 10^-7 टेस्ला ।

प्रश्न 11.
कल्पना कीजिए कि निर्वात में एक वैद्युतचुम्बकीय तरंग का वैद्युत क्षेत्र E = {(3.1 न्यूटन/कूलॉम) cos [(1.8 रेडियन मीटर^-1) y+ (5.4 × 106 रेडियन सेकण्ड^-1)t}}\(\hat{\mathbf{i}}\)
(a) तरंग संचरण की दिशा क्या है?
(b) तरंगदैर्घ्य λ कितनी है?
(c) आवृत्ति υ कितनी है?
(d) तरंग के चुम्बकीय क्षेत्र सदिश का आयाम कितना है?
(e) तरंग के चुम्बकीय क्षेत्र के लिए व्यंजक लिखिए। .
हल’:
दिया है, E = {(3.1) cos [1.8y+ 5.4 × 10⁶ t]}\(\hat{\hat{\mathbf{\imath}}}\).
जहाँ E न्यूटन/कूलॉम में, दूरी मीटर में तथा समय सेकण्ड में है।
इसकी तुलना E = Eo cos (ky + ωt) \(\hat{\hat{\mathbf{\imath}}}\) से करने पर,
k = 1.8 रेडियन मीटर^-1, ω = 5.4 × 10⁶ रेडियन सेकण्ड^-1
E₀ = 3.1 न्यूटन कूलॉम^-1
(a) पद ky में गुणांक y से स्पष्ट है कि यह तरंग ऋणात्मक Y-अक्ष के अनुदिश गतिशील है।
(b)
∵ \(k=\frac{2 \pi}{\lambda} \)
∴ \(\lambda=\frac{2 \pi}{k}\)
या  तरगदध्य तरंगदैर्घ्य \lambda=\frac{2 \times 3.14}{1.8}= 3.48 मीटर ≈ 3.5 मीटर।
= 1.8

(c) ω = 2 πυ से, \(\nu=\frac{\omega}{2 \pi}\)
∴ आवृत्ति \(v=\frac{5.4 \times 10^{6}}{2 \times 3.14}\)
= 8.6 × 10⁵ हर्ट्स
= 0.86 मेगाहर्ट्स।

(d) ∵ E₀ = 3.1 न्यूटन कूलॉम^-1, c = 3 × 10⁸ मीटर सेकण्ड^-1
∴ \(c=\frac{E_{0}}{B_{0}}\) से, चुम्बकीय क्षेत्र का आयाम \(B_{0}=\frac{E_{0}}{c}=\frac{3.1}{3 \times 10^{8}}\)
= 10 × 10^-8 टेस्ला
= 10 नैनोटेस्ला।

(e) ∵ तरंग ऋणात्मक Y-अक्ष की दिशा में गतिशील है तथा वैद्युत क्षेत्र के कम्पन X-अक्ष की दिशा में हैं, अत: चुम्बकीय क्षेत्र के कम्पन Z-अक्ष की दिशा में होंगे। ∴ चुम्बकीय क्षेत्र के लिए व्यंजक ।
B= Bo cos (ky + ωt) \(\hat{\mathbf{k}}\)
= 10 नैनोटेस्ला cos (1. 8 रेडियन मीटर-1 y+ 5.4 x 106 रेडियन सेकण्ड-1t) \(\hat{\mathbf{k}}\)

प्रश्न 12.
100 वाट वैद्युत बल्ब की शक्ति का लगभग 5% दृश्य विकिरण में बदल जाता है।
(a) बल्ब से 1 मीटर की दूरी पर
(b) 10 मीटर की दूरी पर दृश्य विकिरण की औसत तीव्रता कितनी है?
यह मानिए कि विकिरण समदैशिकतः उत्सर्जित होता है और परावर्तन की उपेक्षा कीजिए।
हल:
दृश्य विकिरण में उत्सर्जित शक्ति = \(\frac{5}{100} \times 100\) = 5 वाट
(a)

\(=\frac{5}{4 \times 3.14 \times 1}\) = 0.4 वाट मीटर²।

(b) r = 10 मीटर की दूरी पर औसत शक्ति = \(\frac{5}{4 \times 3.14 \times(10)^{2}}\)
= 0.004 वाट मीटर²।

प्रश्न 13.
em वर्णक्रम (वैद्युतचुम्बकीय स्पेक्ट्रम) के विभिन्न भागों के लिए लाक्षणिक ताप परिसरों को ज्ञात करने के लिए λ_m T= 0.29 सेमी K सूत्र का उपयोग कीजिए। जो संख्याएँ आपको मिलती हैं, वे क्या बतलाती हैं?
हल :
λ_mT = 0.29 सेमी K सूत्र से स्पष्ट है कि 22 को सेमी में प्रयोग किया गया है,
अतः λ_m = λ_m ×10^-8Å
∴ λ_mT = 0.29 सेमी K
⇒ λ_m x 10^-8 × T = 0.29
\(T=\frac{29 \times 10^{6}}{\lambda_{m}(\hat{A})} K\)
(a) λ_m = 10^-12 मीटर = 10^-2Å के लिए, (-किरणे)
T = 2.9 × 10⁹ K.
(b) λ_m = 10^-10 मीटर = 1Å के लिए, (x-किरणे)
T = 2.9 × 10⁷ K.
(c) λ_m = 10^-6 मीटर = 10⁴Å के लिए, (दृश्य प्रकाश)
T = 29 × 10² = 2900 K.
(d) λ_m = 1 मीटर = 10¹⁰ Å के लिए,
T = 2.9 × 10^-3 K आदि।
उक्त परिणाम स्पेक्ट्रम के विभिन्न तरंगदैर्घ्य परास प्राप्त करने हेतु आवश्यक परम ताप प्रदर्शित करते हैं।

प्रश्न 14.
वैद्युतचुम्बकीय विकिरण से सम्बन्धित नीचे कुछ प्रसिद्ध अंक, भौतिकी में किसी अन्य प्रसंग में वैद्युतचुम्बकीय दिए गए हैं। स्पेक्ट्रम के उस भाग का उल्लेख कीजिए जिससे इनमें से प्रत्येक सम्बन्धित है।
(a) 21 सेमी (अन्तरातारकीय आकाश में परमाण्वीय हाइड्रोजन द्वारा उत्सर्जित तरंगदैर्ध्य)
(b) 1057 मेगाहर्ट्स (लैंब-विचलन नाम से प्रसिद्ध, हाइड्रोजन में, पास जाने वाले दो समीपस्थ ऊर्जा स्तरों से उत्पन्न विकिरण की आवृत्ति)
(c) 2.7 K (सम्पूर्ण अन्तरिक्ष को भरने वाले समदैशिक विकिरण से सम्बन्धित ताप-ऐसा विचार जो विश्व में बड़े धमाके ‘बिग बैंग’ के उद्भव का अवशेष माना जाता है।)
(d) 5890 Å – 5896 Å (सोडियम की द्विक रेखाएँ) ।
(e) 14.4 keV [⁵⁷ Fe नाभिक के एक विशिष्ट संक्रमण की ऊर्जा जो प्रसिद्ध उच्च विभेदन की स्पेक्ट्रमी विधि से सम्बन्धित है (मॉसबौर स्पेक्ट्रोस्कॉपी)।
हल :
(a) दी गई तरंगदैर्घ्य 10^-2 मीटर क्रम की है, जो लघु रेडियो तरंग क्षेत्र में पड़ती है।
(b) यह आवृत्ति 10⁹ हर्ट्स की कोटि की है, जो लघु रेडियो तरंग क्षेत्र में पड़ती है।
(c) λ_m T = 0.29 सेमी K से, T= 2.7 कूलॉम के लिए,

यह तरंगदैर्घ्य माइक्रो तरंगों के क्षेत्र में पड़ती है।
(d) दी गई तरंगदैर्ध्य 10^-6 मीटर की कोटि की हैं जो दृश्य विकिरण क्षेत्र में पड़ती हैं।
(e) E = 14.4 kev = 14.4 × 10³ eV
परन्तु \(E=\frac{h c}{\lambda e} \mathrm{eV}\)
∴ संगत तरंगदैर्घ्य \(\lambda=\frac{h c}{e E}=\frac{6.62 \times 10^{-34} \times 3 \times 10^{8}}{1.6 \times 10^{-19} \times 14.4 \times 10^{3}}\)
= 8.6 × 10^-11 मीटर
⇒ λ≈ 10^-10 मीटर = 1 Å
यह तरंगदैर्घ्य x-किरण क्षेत्र में पड़ती है।

प्रश्न 15.
निम्नलिखित प्रश्नों का उत्तर दीजिए
(a) लम्बी दूरी के रेडियो प्रेषित्र लघु-तरंग बैण्ड का उपयोग करते हैं। क्यों?
(b) लम्बी दूरी के TV प्रेषण के लिए उपग्रहों का उपयोग आवश्यक है। क्यों?
(c) प्रकाशीय तथा रेडियो दूरदर्शी पृथ्वी पर निर्मित किए जाते हैं किन्तु x-किरण खगोल विज्ञान का अध्ययन पृथ्वी का परिभ्रमण कर रहे उपग्रहों द्वारा ही सम्भव है। क्यों?
(d) समतापमण्डल के ऊपरी छोर पर छोटी-सी ओजोन की परत मानव जीवन के लिए निर्णायक है। क्यों?
(e) यदि पृथ्वी पर वायुमण्डल नहीं होता तो उसके धरातल का औसत ताप वर्तमान ताप से अधिक होता है या
कम?
(f) कुछ वैज्ञानिकों ने भविष्यवाणी की है कि पृथ्वी पर नाभिकीय विश्व युद्ध के बाद ‘प्रचण्ड नाभिकीय शीतकाल’ होगा जिसका पृथ्वी के जीवों पर विध्वंसकारी प्रभाव पड़ेगा। इस भविष्यवाणी का क्या आधार है?
उत्तर :
(a) ये तरंगें पृथ्वी के आयनमण्डल से परावर्तित होकर वापस पृथ्वी तल की ओर लौट आती हैं और इसी कारण बिना ऊर्जा खोए पृथ्वी पर लम्बी दूरियाँ तय कर पाती हैं।
(b) बहुत लम्बी दूरी के सम्प्रेषण के लिए अति उच्च आवृत्ति की तरंगों की आवश्यकता होती है। आयनमण्डल इन तरंगों को पृथ्वी की ओर परावर्तित नहीं कर पाता। अतः ये तरंगें आयनमण्डल से पार निकल जाती हैं। इन्हें वापस पृथ्वी पर भेजने के लिए उपग्रह की आवश्यकता होती है।
(c) चूँकि पृथ्वी का वायुमण्डल x-किरणों को अवशोषित कर लेता है। अत: x-किरण खगोलविज्ञान का अध्ययन वायुमण्डल से ऊपर उपग्रहों द्वारा ही सम्भव है।
(d) यह ओजोन परत सूर्य से पृथ्वी पर आने वाली मानव जीवन के लिए हानिकारक पराबैंगनी तरंगों को अवशोषित कर लेती है। अतः ओजोन परत, पृथ्वी पर मानव जीवन की सुरक्षा के लिए अति महत्त्वपूर्ण है।
(e) यदि पृथ्वी पर वायुमण्डल नहीं होता तो हरित गृह प्रभाव नहीं होता। इससे पृथ्वी का ताप वर्तमान ताप की तुलना में कम होता।
(f) प्रचण्ड नाभिकीय युद्ध के बाद पृथ्वी धूल तथा गैसों के विशाल बादल से घिर जाएगी जिसके कारण सूर्य की रोशनी पृथ्वी तक नहीं पहुंच पाएगी ओर पृथ्वी बहुत अधिक ठण्डी हो जाएगी।

वैद्युत चुम्बकीय तरंगें NCERT भौतिक विज्ञान प्रश्न प्रदर्शिका (Physics Exemplar Problems) पुस्तक से चयनित महत्त्वपूर्ण प्रश्नों के हल

वैद्युत चुम्बकीय तरंगें बहुविकल्पीय प्रश्नोत्तर

प्रश्न 1.
कार्बन मोनोक्साइड के एक अणु को कार्बन एवं ऑक्सीजन परमाणुओं में विघटित करने के लिए 11 eV ऊर्जा की आवश्यकता होती है। इस विघटन के लिए उपयुक्त वैद्युतचुम्बकीय विकिरण की न्यूनतम आवृत्ति होती है –
(a) दृश्य क्षेत्र में
(b) अवरक्त क्षेत्र में
(c) पराबैंगनी क्षेत्र में
(d) माइक्रोतरंग क्षेत्र में।
उत्तर :
(c) पराबैंगनी क्षेत्र में

प्रश्न 2.
ऊर्जा फ्लक्स 20 W/सेमी² का प्रकाश एक अपरावर्ती पृष्ठ पर अभिलम्बवत् आपतित होता है। यदि पृष्ठ का क्षेत्रफल 30 सेमी² हो तो 30 मिनट में (पूर्ण अवशोषण के लिए) प्रदत्त कुल संवेग होगा –
(a) 36 × 10^-5 किग्रा मीटर/सेकण्ड
(b) 36 × 10^-4 किग्रा मीटर/सेकण्ड
(c) 108 × 10⁴ किग्रा मीटर/सेकण्ड
(d) 1.08 × 10⁷ किग्रा मीटर/सेकण्ड।
उत्तर :
(b) 36 × 10^-4 किग्रा मीटर/सेकण्ड

प्रश्न 3.
100 W के बल्ब से 3 मीटर की दूरी पर पहुँचने वाले विकिरणों से उत्पन्न वैद्युत क्षेत्र की तीव्रता E है। उतनी ही दूरी पर 50 W के बल्ब से आने वाले प्रकार के विकिरणों के कारण उत्पन्न वैद्युत क्षेत्र की तीव्रता होगी
(a) \(\frac{E}{2}\)
(b) 2E
(c) \(\frac{E}{\sqrt{2}}\)
(d) √2E
उत्तर :
(d) √2E.

प्रश्न 4.
यदि E एवं B क्रमशः वैद्युतचुम्बकीय तरंगों के वैद्युत एवं चुम्बकीय क्षेत्र (सदिश) हों तो . वैद्युतचुम्बकीय तरंगों की संचरण दिशा है –
(a) E के अनुदिश
(b) B के अनुदिश
(c) B × E के अनुदिश
(d) E × B के अनुदिश ।
उत्तर :
(d) E × B के अनुदिश ।

प्रश्न 5.
वैद्युतचुम्बकीय तरंग की तीव्रता में वैद्युत एवं चुम्बकीय क्षेत्र घटकों के योगदानों का अनुपात होता है
(a) c : 1
(b) c² : 1
(c) 1  :1
(d) √c : 1.
उत्तर :
(c) 1 : 1

प्रश्न 6.
एक द्विध्रुव ऐन्टिना से वैद्युत चुम्बकीय तरंगें बाहर की ओर विकिरित होती हैं जिनके वैद्युत क्षेत्र सदिश का आयाम E₀ है। वैद्युत क्षेत्र E_o, जो ऊर्जा संचार का प्रमुख वाहक है, स्रोत से दूरी के साथ इसका परिमाण –
(a) \(\frac{1}{r^{3}}\) के अनुसार घटता है …
(b) \(\frac{1}{r^{2}}\) के अनुसार घटता है ..
(c) \(\frac{1}{r}\) के अनुसार घटता है
(d) अचर बना रहता है। [
उत्तर :
(c) \(\frac{1}{r}\) के अनुसार घटता है

वैद्युत चुम्बकीय तरंगें अति लघु उत्तरीय प्रश्नोत्तर

प्रश्न 1.
किसी सुवाह्य रेडियो का प्रसारक स्टेशन के सापेक्ष अभिविन्यास महत्त्वपूर्ण क्यों होता है?
उत्तर :
वैद्युतचुम्बकीय तरंगें समतल ध्रुवित होती हैं, अत: अभिग्राही ऐन्टिना इन तरंगों के वैद्युतचुम्बकीय भाग के समान्तर होना चाहिए।

प्रश्न 2.
माइक्रोवेव ओवन जल अणु युक्त खाद्य पदार्थ का ऊष्मन सर्वाधिक प्रभावी ढंग से क्यों करता है?
उत्तर :
माइक्रोवेव ओवन जल अणुयुक्त खाद्य पदार्थ का ऊष्मन सर्वाधिक प्रभावी ढंग से करता है क्योंकि माइक्रोवेव की आवृत्ति, जल के अणुओं की अनुनाद आवृत्ति के बराबर होती है।

प्रश्न 3.
किसी समान्तर प्लेट संधारित्र पर आवेश q= q_o cos 2πυt के अनुसार परिवर्तित होता है। इसकी प्लेटें बहुत विशाल (क्षेत्रफल = A) हैं और एक-दूसरे के बहुत पास-पास रखी हैं (पृथकन = d)। कोर प्रभावों को नगण्य मानते हुए संधारित्र में विस्थापन धारा की गणना कीजिए।
उत्तर :
संधारित्र में विस्थापन धारा I_D = I_C = \(\frac{d}{d t}\left(q_{0} \cos 2 \pi v t\right)\)
= q_o (- sin 2πυ t) × 2πυ
= -q_o 2 πυ.sin 2 πυ t

प्रश्न 4.
परिवर्तनीय आवृत्ति का एक ac स्रोत एक संधारित्र से जुड़ा है। आवृत्ति में कमी करने पर विस्थापन धारा किस प्रकार प्रभावित होगी?
उत्तर :
संधारित्र का धारितीय प्रतिघात \(\left(X_{C}\right)=\frac{1}{\omega C}=\frac{1}{2 \pi f C}\)
आवृत्ति f कम करने पर, धारितीय प्रतिघात X_C बढ़ेगा जिसके परिणामस्वरूप चालन धारा (I_C) घटेगी। परन्तु I_C = I_D, अत: विस्थापन धारा कम हो जाएगी।

वैद्युत चुम्बकीय तरंगें लघु उत्तरीय प्रश्नोत्तर

प्रश्न 1.
वैद्युतचुम्बकीय तरंगें जिनकी तरंगदैर्ध्य –
(i) λ₁ है, उपग्रह संचार में प्रयुक्त होती हैं। .
(ii) λ₂ है, जलशोधित्रों में जीवाणुनाश के लिए प्रयुक्त होती हैं।
(iii) λ₃ है, भूमिगत पाइप लाइनों में तेल के रिसाव के संसूचन के लिए उपयोग में लायी जाती हैं।
(iv) λ₄ है, धुंध और कोहरे की स्थिति में वायुयान उड़ान पथ पर दृश्यता में सुधार लाने के लिए उपयोग में लायी जाती हैं।
(a) इन वैद्युतचुम्बकीय विकिरणों को पहचानिए और बताइए कि ये वैद्युतचुम्बकीय स्पेक्ट्रम के किस भाग से सम्बन्धित हैं।
(b) इन तरंगदैर्यों को परिमाण के बढ़ते क्रम में व्यवस्थित कीजिए।
(c) प्रत्येक की एक अन्य उपयोगिता लिखिए।
उत्तर :
(a) λ₁ → सूक्ष्म तरंगें या माइक्रोवेव
λ₂ → पराबैंगनी तरंगें
λ₃ → x-किरणें
λ₄ → अवरक्त किरणें
(b) λ₃ < λ₂ < λ₄ < λ₁
(c) सूक्ष्म तरंगें → रेडार
पराबैंगनी तरंगें → नेत्र शल्यता
x-किरणें → अस्थिभंग क्रमवीक्ष्ण
अवरक्त किरणें → प्रकाशीय संचार

वैद्युत चुम्बकीय तरंगें आंकिक प्रस्नोत्तर

प्रश्न 1.
आपको एक 2 μF का समान्तर प्लेट संधारित्र दिया गया है। आप इसकी प्लेटों के बीच के अन्तराल में 1 मिलीऐम्पियर की तात्क्षणिक विस्थापन धारा कैसे स्थापित करेंगे?
हल :
दिया हैं, C = 2 μF = 2 × 10^-6F, I_D = 10^-3 मिलीऐम्पियर
विस्थापन धारा (I_D) = C \(\frac{d V}{d t}\) × 1 × 10^-3 = 2 × 10^-6 \(\frac{d V}{d t}\)
∴ \(\frac{d V}{d t}\) = \(\frac{1}{2}\) × 10³ = 500 वोल्ट/सेकण्ड
अत: 500 वोल्ट/सेकण्ड की दर से परिवर्तित विभवान्तर लगाकर लक्षित विस्थापन धारा उत्पन्न सकेगी।

MP Board Class 12th Physics Solutions

MP Board Class 12th General Hindi व्याकरण अशुद्ध गद्यांश की भाषा का परिमार्जन

भाषा का शुद्ध और स्पष्ट लेखन उस समय तक सम्भव नहीं है, जब तक कि शब्दों और उनके अर्थ के विषय में पूर्ण ज्ञान न हो। शुद्ध वाक्य रचना के लिए अशुद्धियों पर ध्यान देना बड़ा आवश्यक है। अशुद्ध वाक्य उतना ही भद्दा और अरुचिपूर्ण लगता है जितना कि बेतरतीब बनाया हुआ भोजन। अतः अशुद्धियों का विवरण नीचे दिया जा रहा है-

1. लिंग सम्बन्धी अशुद्धियाँ – संज्ञा शब्दों में लिंग – परिवर्तन होता है; जैसे –

2. वचन सम्बन्धी अशुद्ध याँ
1. वह किसके कलम है – वह किसकी कलम है।
2. उसका भाग्य फूट गया – उसके भाग्य फूट गए।
3. मेरे बटुआ उड़ गया – मेरा बटुआ उड़ गया।
4. क्या तेरा प्राण निकल रहा है क्या तेरे प्राण निकल रहे हैं।

3. समाज सम्बन्धी अशुद्धियाँ

4. संधि समास अशुद्धियाँ
1. निरस – नीरस (निः + उक्त)।
2. उपरोक्त – उपर्युक्त (उपरि + उक्त)।
3. सदोपदेश – सदुपदेश (सद् + उपदेश)।

5. कर्ता और क्रिया का समान न होना – कर्ता और क्रिया के वचन, लिंग और पुरुष समान होने चाहिए। यदि ऐसा न हुआ तो वाक्य अः शुद्ध हो जाता है। उदाहरण के लिए –

6. शब्दों को यथा स्थान रखना – वाक्य में कर्ता, कर्म, करण, विशेषण, विशेष्य, क्रिया – विशेषण आदि के स्थान निश्चित होते हैं। यदि वे निश्चित स्थान पर न रखे
गए अथवा उनका स्थान बदल दिया गया तो वाक्य अशुद्ध हो जाता है।

7. अनावश्यक शब्दों का प्रयोग

8. वर्ण और मात्रा संबंधी अशुद्धियाँ

महत्त्वपूर्ण परीक्षोपयोगी प्रश्न

निम्नलिखित वाक्यों के शुद्ध रूप लिखिए
1. इन्दिरा गाँधी की मृत्यु पर भारत में दुःख छा गया।
2. मैं कल आगरा से वापस लौटूंगा।
3. तुमने यह काम करना है।
4. कोप ही दण्ड का एक विधान है।
5, आग में कई लोगों के जल जाने की आशा है।
उत्तर –
1. इन्दिरा गाँधी की मृत्यु पर भारत में शोक छा गया।
2. मैं कल आगरा से लौटूंगा।
3. तुम्हें यह काम करना है।
4. दण्ड ही कोप का एक विधान है।
5. आग में कई लोगों के जल जाने की आशंका है।

निम्नलिखित अशुद्ध शब्दों को शुद्ध कीजिए-

अभ्यास के लिए कुछ महत्त्वपूर्ण प्रश्न
(i) अभ्यास के लिए शुद्ध – अशुद्ध वाक्य।

1. संग्रहित
(क) संघरित (ख) संगृहीत (ग) संग्रहीत (घ) संघह्वीत
उत्तर –
(ख) संगृहीत।।

2. प्रथक
(क) पृथक् (ख) पिरथक (ग) परथिक (घ) पिर्थक
उत्तर –
(क) पृथक्।

3. उज्जवल
(क) उजवल (ख) उज्ज्वल (ग) उजवल्य (घ) उज्जवल
उत्तर –
(ख) उज्ज्वल

4. प्रनाम
(क) पिरणाम (ख) पिरनाम (ग) पृणाम (घ) प्रणाम
उत्तर –
(घ) प्रणाम।।

5. भैंस और बैल खड़े हैं
(क) भैंस खड़ा और बैल खड़ी है। (ख) भैंस और बैल दोनों खड़ी हैं। (ग) भैंस और बैल खड़ा हुआ है। (घ) भैंस और बैल दोनों खड़े हैं।
उत्तर –
(घ) भैंस और बैल दोनों खड़े हैं।

6. आगरा के अन्दर हैजा का जोर है
(क) आगरा के अन्दर हैजा (ख) हैजा का जोर है आगरा में। का प्रकोप है। (ग) हैजा का प्रकोप है आगरा में। (घ) आगरा में प्रकोप है हैजा का।
उत्तर –
(घ) आगरा में प्रकोप है हैजा का।

7. उसे अनुत्तीर्ण होने की आशा है
(क) आशा है उसे अनुत्तीर्ण (ख) अनुत्तीर्ण होने की उसे आशंका होने की। (ग) उसे आशंका है अनुत्तीर्ण (घ) उसे अनुत्तीर्ण होने की आशंका होने की।
उत्तर –
(घ) उसे अनुत्तीर्ण होने की आशंका है।

(ii) शब्दों के क्रम संबंधी अशुद्धियों को शुद्ध कीजिए
अशुद्ध – राम, जो कल भूखा था, ने अभी तक कोई भोजन नहीं किया।
शुद्ध – राम, जो कल भूखा था अभी तक भोजन नहीं किया।
अशुद्ध – राम बाजार से फूलों की माला एक लाई।।
शुद्ध – राम बाजार से एक फूलों की माला लाया।
अशुद्ध – सब लड़कियाँ अपनी किताब और कल से लिख और पढ़ रहे थे।
शुद्ध – सब लड़कियाँ अपनी किताब और कलम से पढ़ ओर लिख रही थीं।

(iii) प्रत्यय संबंधी अशुद्धियाँ दूर कीजिए
अशुद्ध – राम यह कार्य आवश्यकीय है।
शुद्ध – राम यह कार्य आवश्यक है।
अशुद्ध – आपकी सौजन्यता से मेरे पुत्र को नौकरी मिल गई।
शुद्ध – आपके सौजन्य से मेरे पुत्र को नौकरी मिल गई।
अशुद्ध – साधु के माथे पर रामानन्द तिलक है।
शुद्ध – साधु के माथे पर रामानन्दी तिलक है।

(iv) अनुस्वार एवं चन्द्र बिन्दु संबंधी अशुद्धियाँ शुद्ध कीजिए–

MP Board Class 12th Hindi Solutions

MP Board Class 12th Special English Model Question Paper

Time : 3 Hours
Maximum Marks : 100

Instructions:

1. Attempt all the questions.
2. Read the questions carefully and do accordingly.
3. Marks allotted to each question are indicated against it.

Unit 1

1. Read the passage carefully and answer the questions given below it:
Human beings are made up mostly of water, in roughly the same percentage as water is to the surface of the earth. Our tissues and membranes, our brains and hearts, our sweat and tears-all reflect the same recipe for life, in which efficient use is made of those ingredients available on the surface of the earth. We are 23 percent carbon, 2.6 percent nitrogen, 1.4 percent calcium, 1.1 percent phosphorus, with tiny amounts of roughly three dozen other elements. But above all we have oxygen (61 percent) and hydrogen (10 percent), fused together in the unique molecular combination known as water, which makes up 71 percent of the human body.

Questions:
(i) What are the contents of a human body? [2]
(ii) The word ‘efficient’ means: [1]
(a) Capable (b) difficult (c) noteworthy (d) Easy.
(iii) Give opposite word for ‘roughly’. [1]
(iv) Give noun form of the word ‘reflected’. [1]
Answers:
(i) The contents of human body are water, carbon, oxygen, nitrogen, calcium, phosphorous, hydrogen and some other elements.
(ii) (a) Capable.
(iii) exactly.
(iv) reflection.

2. Read the following extract carefully and answer the questions given below it.
An intellectual hatred is the worst,
So let her think opinions are accursed
Have I not seen the loveliest woman born
Out of the mouth of Plenty’s horn
Because of another opinionated mind
Barter other horn and every good
By quiet.natures.understood
For an old bellows full of angry wind.

Questions:
(i) What is the worst kind in poet’s eyes? [1]
(a) angry wind (b) quiet nature (c) opinions (d) intellectual hatred.
(ii) ‘Opinionated’ means [1]
(iii) Make noun from the word intellectual. [1]
(iv) What are the evil effects of ‘Horn of plenty’? [2]
Answers:
(i) (d) intellectual hatred.
(ii) ‘Opinionated means-having very strong opinions that you are not willing to change.’
(iii) Intellect.
(iv) It gives birth to hatred to mankind as it gives abundance so who do not have it becomes jealous of others.

3. Answer any six of the following questions in about 30 words each. [6×2 = 12]

(i) How did Madam Forestier react when Mathilde returned the necklace?
Answer:
When Mathilde returned the necklace Madame Forestier reacted that she (Mathilde) should have returned it sooner. She (Forestier) might have needed it.

(ii) What threat do rising sea levels pose to human population?
Answer:
Rising sea levels will lead to loss of low-lying coastal areas around the world which will further give rise in number of refugees as one-third of population live within sixty kilometers of coastline.

(iii) Why should the youth form the vanguard in all activities?
Answer:
Theyouths should form the vanguara in all activities for they have the capacity to resist aggression and at this critical juncture its power must be mobilized.

(iv) What does Albert mean by civilized human beings?

(v) What was Netaji’s proposal during the annual session of the Indian National Congress?
Answer:
Netaji proposed that the congress should at once send an ultimatum to the British government demanding independence within six months or prepare immediately for a national struggle.

(vi) Why has Surat been mentioned in the poem ‘Goodbye Party for Miss Pushpa T.S.’
Answer:
Surat has been mentioned in the poem because the poet is confused about the place Pushpa’s father belonged to and also the poet remembers his stay at Surat once.

(vii) What helps the poet balancing his weight on the ladder round?
Answer:
The instep arch helps the poet in balancing his weight on the ladder-round.

4. Answer any two of the following questions in about 75-100 words. [2 x 4 = 8]

(i) How has the Casuarina tree been personified in the poem?
Answer:
‘Our Casuarina Tree’ is a poem written to express the feeling of the poetess. It is not merely the description of a tree but it is a tribute to the tree. The poetess presonifies the tree. She bestoWs alihuman feelings to the tree. The generous attitude of the tree is great. The tree comforts all. It also shares the joys and sorrows of the human beings. The poetess feels the tree shedding tears and lamenting at the death of her brother and sister. The tree is also destined to die like human being. Thus, it has been personified. It is not unaffected from human curses as well.

(ii) Analyse the poem ‘On this Being Arrived at the age of Twenty Three’ as a Petrachan Sonnet.
Answer:
Sonnet is a short poem of fourteen lines expressing a single thought or emotion at a time. It owes its popularisation to the 14th century Italian poet Francsco Petrarch who used this poetic form to express his love for his idealised lady love, Laura. John Milton uses the original Italian (Petrarchan) form to express his devotion to God or sublime feelings. hi this form, the poem is divided into two parts—the octave (a stanza of eight lines) and the sestet (a stanza of six lines). The first part makes a statement or puts up a question while the second part illustrates or serves the answer to it. On Being Arrived at the Age of Twenty-three is a devotional sonnet in Petrarchan form. It is a striking example of the Renaissance ethos and Reformation zeal. It is an assertion of faith and a wish to be guided by the divine will.

(iii) Justify the statement that ‘Dream Children: A Reverie’ is a lyric in prose.
Answer:
Dream Children: A Reverie is an outburst of a flow of imagination of Charles Lamb. Lamb was said to be the Prince of English essayists. He wrote this essay when he was nearing his fifties. As his life was not at all happy and comfortable, he towards the end of his life, has expressed his dreams which couldn’t be fulfilled during his lifetime. He had suffered a lot in his life. He himself was lame. His elder brother whom he loved so much died in great pain. He missed him because he usually carried him on his back when he could not walk. In his youth, Lamb had a disappointing love-affair with a girl who afterwards married another man. He was a bachelor. He lived in utter loneliness. Though he wanted a family and children but they were denied to him in his actual life. In this essay he is dreaming for having two children, on both of his sides behaving like real children. Although the story has created a moving life situation which has all the elements of a lyric. This is a flow which makes one completely engrossed with the story

Unit 2: Grammar

5. Do as directed (any Five). [5 x 1 = 5]
(i) Rewrite the following sentence by using ‘it’: To see you is a real pleasure.
Answer:
It is a real pleasure to see you.

(ii) People expect better results this time. (Change the voice)
Answer:
Better results are expected this time.

(iii) Ronak does his work properly. (Make a negative sentence)
Answer:
Ronak does not do his work properly.

(iv) The teacher said, “Man is Moral”. (Change the narration)
Answer:
The teacher told that man is moral.

(v) The toys are very expensive. We can’t afford to buy them. (use ‘so that’ and rewrite the sentence)
Answer:
The toys are so expensive that we can’t afford.to buy them.

(vi) Use the proper determiner (Are there letters for me.) (some/any/much)
Answer:
Any.

(vii) The book is lost that you gave me yesterday.(Combine the sentence to make a complex sentence)
Answer:
The book you gave me yesterday is lost.

6. Do as directed. [5 x 1 = 5]
(i) Give syllable division of the word ‘department’.
(ii) How many syllables does the word ‘examination’ have?
(iii) Head, bend, cattle, men. (Pick out the odd one)
(iv) Write down the word which has (VC syllable)
(v) Mother Teresa won many international (award/awards)
Answer:
(i) department,
(ii) 4 syllables,
(iii) bend,
(iv) pen,
(v) awards.

Unit 3: Fiction

7. Answer any one of the following questions (120 words) [5]
(i) Describe how Swaminathan passed Monday in his school.
Answer:
Swami is a student of the First Form (Section A). It is Monday morning and Swami hates Mondays, for it means activity, discipline and work, after his enjoyment on Saturday and Sunday. As Swami sits on the table in his ‘room’—which is merely a table in the dressing- room of his father—he finds that he has a lot of home work to do, and only two hours for doing it. He feels bored and tired, and is in no mood for work.

He reaches the class on time and we are introduced to the fire-eyed teacher Vedanayagantie class-teacher and also arithmetic teacher. Swami does not like hini and we get a taste of Narayan’s verbal humour when we are told that Swami’s “çriticism of the teacher’s face was that his eyes were too near each other, that there was more hair on his chin than one saw from the bench, and that he was very very bad-looking.” All the sums done by Swami are wrong, they are crossed out, the remark ‘very bad’ is given, he is very severely pinched over his left ear, and told to go back to his seat.

Then comes the History period, and the teacher is Dr Pillai. His method of teaching is interesting, but it does not conform to any known principles of education. It is followed by the scripture period and the teacher, Ebenczar, is a fanatic Christian. He constantly criticises and abuses 1-lindu Gods who, for him, are merely pieces of stone.

(ii) Imagine yourself as Swaminathan and narrate the following incident: Encounter between Mani and Rajam near Nallapp’s grove.
Answer:
Mani was my best friend. He had a good personality. He never cared for study. He never brought any book to the class and never bothered about homework. He always bullied all strangers who came his way, be they big or small but, one day, a new entrant, Rajam, came as ¿i challenge for him. Rajam was the son of the Superintendent of Police. He was well-mannered, well-dressed and also a brilliant student. He became a rival to Mani. Mani challenged him and invited him at Nallappa’s grove on the river side to decide who was superior. They reached there—Mani with his club and Rajam with his airgun. Mani was thinking, now he woutd teach Rajam a lesson. He would break his neck and kill him. Then Rajam came and each of them blamed each other. Mani said that Rajam shouldn’t have brought gun and Rajam said that Mani shouldn’t have brought his club. However, after a long discussion, they withdrew. Raam and Mani became friends. Rajam offered chocolate. I was happy for I had managed for all these.

8. Answer ‘any five’ of the following questions in 30 words. [5 x 2 = 10]
(i) What were the similarities between Swaminathan and Samuel, the Pea?
Answer:
(Md’. Board 2009)
Swami’s another bosom friend was Samuel, the Pea. He was called the Pea as he was very small in size. There is nothing uncommon about him, for he is neither a good student nor physically remarkable. The only similarity between them was laughter. They were ab1eo see together the same absurdities and incongruities in things. The most trivial and unnoticeable things to others would tickle them to death.

(ii) What did Mani decide to do with Rajam?
Answer:
Mani didn’t like Rajam. Rajam made a good impact in class and also in school. Mani grew jealous of him. So, Mani wanted to bundle him into the river or to crack his shoulders with his club. Mani wanted to have a duel with Rajam. He was raging in anger and wanted to break his bones.

(iii) Describe Swaminathan’s state of mind when Sankar, Somu and others stopped talking to him.
Answer:
Swami was feeling restless when Sankar, Somu, and others stopped talking to him. He was feeling lonely His friends were also hostile to him. It was very painful for poor Swami but he could not help it. He wanted to talk to them and crack jokes but he was helpless. He was feeling uncomfortable.

(iv) What did the Headmaster ask the students to do during the vacation?
Answer:

The headmastét came and announced the closure of school for the vacation. He also hoped that the boys would not waste their time but read story-books and keep glancing through the books prescribed for their next classes to which it was hoped they would be promoted.

(v) Why was Swaminathan cold and reserve to his mother when he was taken to her room?
Answer:
Swammatban’s mother was in labour pain. She had been in bed for two days. Swami didn’t see her in kitchen. He felt uncomfortable in her absence. When he was taken to her room, he found her lying weak and pale on the bed. She called him closer to her. As Swami was not so mature, he couldn’t understand what was going on. He was cold and reserved when he came in the room.

(vi) How did Mani contemplate taking revenge on Somu, Sankar and the Pea?
Answer:
Mani contemplated taking revenge on Somu, Sankar and the Pea by breaking Somu’s waist, then he will get Pea under his heel and press him to earth and finally he will hang Sankar by his neck over Sarayu from Peepul branch.

Unit 4: Drama

9. Answer any one of the following questions in (120 words) [5]

(i) Give an account of the way the Silver Box was recovered from the residence of Jones.
Answer:
When Mrs Jones detects the stolen purse, she thinks to return it to he; employet So, when Jones is out she shakes out his coat. The silver box falls down from the coat pocket. She looks hard at it but Jones snatches it from her hands with a promise that he would throw it away into the river along with the purse. On the other hand, when Barthwick finds the box missing, he asks Snow, a detective, to search it. Snow, out of doubt, comes to Jones house just at the time when Jones is trying to take the box from his wife who takes it to go to return it to Borthwick. Snow detects the letters J.B. carried on it and is sure it was the stolen one from Barthwick’s house.

(ii) What shortcomings of the British Judicial System emerge out of the play ‘The Silver Box’.
Answer:
The Silver Box may be regarded as a problematic play. It is a social tragedy. The victims are poor Jones, his wife and children. The victimizer in the case is not so much the wealthy liberal, Mr. Barthwick as law itself. Galsworthy indicts the established institution of law courts which is held in the highest ešteem for its fairness. The ground reality is that the scales of justice are tilted in favour of men of position and wealth. The principle of equality before law is a paper tiger, a legal fiction. Jack and Jones are equally wicked. Both are eqùally guilty of misconduct, moral degradation and stealing but the law treats them differently. Jack is able to get the support and protection provided by his father, the advocate, and the constable. His offence of stealing is ignored and the Magistrate acquits hjm. However poor Jones who pleads his case himself, is silenced and sent to prison. The clear message conveyed by the play is that Justice is not blind, she is just ashamed to watch.

10. Attempt any five of the following questions [30 words each] [5×2 = 10]

(i) What would the members of the. Labour Party do, according to Mr. Barthwick, once they came to power?
Answer:
Acording to tr Barthwick, the Members of the Labour Party would deprive the upper classes of their rights and property once they came to power.

(ii) What makes the unknown lady meet young Jack so early in the morning?
Answer:
She met young Jack so early in the morning because her crimson silk purse had been stolen and she had seen Jack Barthwick stealing it.

(iii) What excuse did Jones provide for picking up the Silver Box?
Answer:
He said that he was not a thief. Whatever he did was because of his drunken state.

(iv) What questions did Jones ask Jack when the case was in progress before the magistrate?
Answer:
jons asked Jack, “Don’t yoù remèmber you said you were a Liberal, same as your father, and you asked mc what I was?”

(v) why does Jones give a blow to snow?
Answer:
Because Jones knows that he was innocent.

(vi) Describe in your own words the room in which the Jones lived.
Answer:
The room in which the Jones lived was a base one with tattered oilcloth and damp, distempered walls. It has an air of tidy wretchedness.

Unit 5: Reading Unseen
11. Read the following passage carefully and answer the questions that follow. [4 + 6 = 10]
Twin top rankings reflect rise of Women in Indian Sports: Saina Nehwal After reclaiming the top spot in badminton Singles rankings, Saina Nehwal is doubly delighted at fellow Hyderabadi tennis ace Sania Mirza’s rise to the summit of the Womens’ Doubles rankings and says the twin achievements reflect the rise of women power in the domain of Indian sports.

“Sania Mirza is a big name in the world of tennis, she is the number one in her game. I wish her all the best in her future endeavors” Saina said on Sunday.

“Women in sports have come up in a big way in recent past and I congratulate all of them, including Mary Kom, Krishna Poonia, Geeta Phogat, Babita Kumari, Heena Sidhu and Sania Mirza,” she said.

“It is good that women power is visible in sports,” she said, crediting the central government’s sports policies for the success stories. Sania was elevated to the No. 1 spot in the Women’s Doubles rankings, according to the latest Women’s Tennis Association (WTA) list released on April 13.
Saina became the first Indian women to be crowned World No.l on March 29 after her Indian Open Grand Prix triumph. But she dropped to the second place, overtaken by China’s Li Xuerui, following her semi-finals exit in the Malaysia Open Super series. But she regained the top slot after Li pulled out of Singapore Open Super Series.

Sania, on the other hand, leap frogged to the top spot after winning her third consecutive Women’s Tennis Association (WTA) title-The Family Circle Cup-with new partner Martina Hingis.

“I am proud to be World No. 1 in badminton. It is really tough to reach the pinnacle in badminton… it took me five years to realise my dream as I became World No. 2 in 2010”, The right-handed shuttler said.

The 25-year-old Saina is the only non-Chinese to get tire top billing since 2010 when Denmark’s Tine Raun ruled the rankings. The 2012 Olympic Games bronze medalist dedicated her recent feat to her parents, coaches and well-wishers.

When asked what makes a Chinese player so tough to beat, she said: “May be these players are trained on best infrastructure they have created for each sport and the availability of best coaches compared to India and other countries where hardly a few best coaches are available.”

“The number of players (in China) is also very high compared to us where there is a shortage of players.”

“Luckily I started my career on best infrastructure created in India at Gopi’s (Pullela Gopichand) Academy at Hyderabad in 2004 and continued till 2014 during which I won national Championships, Junior World Cup and some of Super Series and Gold Grand Prix Tournaments,” she added.

Saina has clinched gold in the 2010 Commonwealth Games and bronze in the 2006 edition, besides picking up a bronze at the Incheon Asian Games last year.

In 2014, she became the first Indian woman to win the China Open Super Series Premier beating Japan’s Akane Yamaguchi in the final.
In another first for Indian women shuttlers, Saina reached the All England open Badminton final last month, but lost to Spain’s Carolina Marin recently.

In 2014, Saina shifted to Prakash Padukone s academy in Bangalore. Since then she has been under the tutelage of Vimal Kumar. Former men’s No. 1 player Padukone also gave her valuable tips.

Saina credited ex-coach Gopichand and incumbent Vimal Kumar for her success. “Both of them are the best of badminton coaches in India. With Gopi sir, I won a number of tournaments and now with Vimal sir my progress is visible in the last seven months,” she said.

With expectations climbing high with each day, Saina said her ultimate aim is the Olympics games.

“I, as a badminton player, will give my 100 percent for my sport. I have to show better results in the World Cup. Many Super Series are lined up” the star said.

Questions:
(i) Delighted mean. [1]
Answer:
Very happy.

(ii) Elevated means [1]
Answer:
High in rank.

(iii) Give a word similar in meaning to ‘triumph’. [1]
Answer:
Victory.

(iv) Clinched means (in a word). [1]
Answer:
Succeeded.

(v) Explain: she is the number one in her game. [2]
Answer:
Sania Mirza is number one in her game i.e. tennis.

(vi) What did Saina tell when asked what makes a Chinese player so tough to beat? [2]
Answer:
She said that there is a possibility that Chinese players were trained on best infrastructure they had created for each sport and the availability of best coaches compared to India and other countries where hardly a few best coaches were available.

(vii) Name the women sports persons whom Saina congratulated. [2]
Answer:
Name of the women sports persons whom Saina congratulated are-Mary Kom, Krishna Poonia, Geeta Phogat, Babita Kumari, Heena Sidhu and Sania Mirza. Read the following poem carefully and answer the questions that follow. [5]

12. Read the following poem carefully and answer the questions that tollow.
Happiness is like a crystal,
Fari and exquisite and clean,
Broken in a million pieces,
Shattered, scattered far and near.
Nov and then along life’s pathway.
Like, some showing fragments fall;
But these are so many pieces
No one ever finds them all

Questions :
(i) The poet compares happiness with. [1]
Answer:
Crystal.

(ii) No one ever finds them all meAnswer: [1]
Answer:
It means ‘no one gets complete happiness’.

(iii) Give opposite word for ‘exquisite’? [1]
Answer:
Ugly.

(iv) What dees the poet want to say here? [2]
Answer:
The poet here wants to say that happiness is scattered here and there in man’s pathway. Now it is upto man how much happiness he manages to get.

Unit 6: Writing/Essay

13. Write an essay on any one of the following topics in about 250 words: [7]
(i) Pollution: A Treat to our Life.
(ii) Politics of Coalition in India.
(iii) My Favourite Game.
(iv) A Visit to a Historical Place.
Answer:
(ii) Politics of Coalition in India
At present Indian politics is under the process of development. Although right from the time of freedom movement the process is on but during the last twenty years there have been a lot of changes. Due to selfish motto of political parties, the aim of getting power to rule things has gone the worst.

Indian politics has lost the real component of fair practice in politics. The means should be right and pure to achieve the object but in our country now the attraction of power is so much that nobody cares for the meAnswer: For example, for winning the election they adopt all those malpractices which are immoral in our society. After election horse-trading goes on to capture power. Ministers, officials and leader of political parties adopt immoral ways and means to earn money.

After 2000, many cases of corruption were detected in public life in which leaders, Government officials, servants, contractors, brokers and anti-social elements were involved. The fashion and tradition of commission increased the corruption in all walks of life. During the last ten years, there were a lot of scandals in which so many, ministers, secretaries, directors, government officers and servants are found involved. The cases of share scandal, hawala, 2G and Coal are the worst which have opened the new chapter of corruption in public life. Though these scandals are mere examples, there are a lot of such scandals which are still to be brought into light. Indeed there is a lot of corruption in our public life. Bribery has become a courtesy. No work is done without it. Almost all the measures adopted to control it have failed head long, because most of our leaders, political workers, government officers, public servants, contractors, brokers, businessmen, traders, industrialists are directly or indirectly involved in the cases of corruption. Some of them have been caught while the others are still beyond reach.

At present even the representatives of people such as some of the MLAs, MPs and ministers, government officers and servants are following the path of corruption and they are making hay while the sun shines. The whole system has become so spoiled and corrupt that it needs well planned serious efforts.

As now-a-days no party is getting absolute majority at the centre so the politics of coalition is going on. It is giving us weak governments. Moreover, the country has to fall to mid term polls due to coalition politics. This new trend now seems to be the way of Indian politics. In coalition form of govt, it becomes very critical for one to run the of govt, and control the parties of different ideas. For example two successive govt, had ruled India-one the NDA and now the UPA. This trend is not at all good for the nation.

But a change in this trend has been seen during the 2014 Lok Sabha Election. Though still a coalition, BJP could get itself 285 seats in Lok Sabha which is sufficient enough to form the government. So the coalition era may end if the unstability and policy created continues in politics.

14. You are Gaurav. You have read the following news article. (4)
At the heart of the literacy campaign is the volunteer, who as instructor, resource person or local organizer, gives freely his/her time and puts in enormous effort to make the campaign succeed.

You have decided to speak at the school assembly on the experience of students who volunteer to take literacy classes. Prepare the speech taking help from the news article and your own view. (50 words)

Or

Write a report on the Annual Day celebration in your school. You are Sukhbir of New Bhopal Academy.
Answer:
Illiteracy is one of the major problems that confront our country. This problem assumes alarming proportions because of the democratic rule in our country. Democracy, which postulates enlightenment, is by and large a blessing, and illiteracy, which implies ignorance, is therefore a curse.

To eradicate illiteracy to some extent, various students volunteets to take literacy classes and feel proud to help their unfortunate countrymen who have been deprived of the privilege of being educated. These voluntary workers, after receiving certain incentives and being provided with the requisite facilities ensure better results in the social arena. They have adopted new paths and motivated a large section of masses towards their literacy classes. This voluntary service on the part of students, has proven to be an effective measure for reaching out to the uneducated masses and thereby further helped the illiterate persons to eradicate their constant exploitation and humiliation at the hands of society. The students have helped these people to become aware of the benefits of being literate/ educated. They have also helped the illiterate persons to move towards a positive change.

By undertaking this creditable, but herculean task, these students feel a sense of pride in being able to make their contribution to take their country on the path of fast growth and progress.

MP Board Class 11th English Solutions

MP Board Class 12th Special English Writing Short Composition

1. Robert of Class XII is not coming to school because he is suffering from fever. He wants you to write an application to the Principal to excuse his absence from school for a week: Write this letter on his behalf. (M.P. Board 2009)
Answer:
The Principal
Sr. Sec. School
XYZ Block
New Delhi
19th December, 20xx

Subject: Leave application due to fever.

Sir,
I am David of Class XII. I am, on behalf of Robert writing this letter to you g. to inform you that he will be unable to attend the school from 17 Dec. 20xx as he has been suffering from typhoid fever. He is taking strong medicines to relieve himself of the disease but it will still take him about one more week to get well. At present he is unable to even write, so I am writing this application on his behalf. Please grant him one week’s leave. He will make up for the classes. I am sure you will understand his plight and grant him leave.

Thanking you.

Yours sincerely
‘David,
XII-A

2. Abhishek of 8, Indira Nagar, Bhopal is not happy with the sanitary conditions of his locality. He decides to write a letter to the local sanitary Inspector of the town to look into the sorry state of affairs. Write a letter on his behalf. (M.P. Board 2009)
Answer:
The Sanitary Inspector
Bhopal Municipal Corporation
Bhopal
27th November, 20xx ,

Subject: Complaint regarding poor sanitary conditions.

Sir,
I am Abhishek, a local resident of 8, Indira Nagar, Bhopal. It is unfortunate that the local civic bodies have remained indifferent towards the cleaning of Indira Nagar locality. Our area presently is in a sorry state of affairs. There are no sweepers to clear the heaps of garbage that lie unattended and start emitting foul smell. The garbage also attracts street dogs and pigs who are keen on rolling over there. The drains of our locality are perpetually blocked and this creates totally insanitary and unhygienic conditions. Installation of dust-bins in the locality has not really helped to improve the situation because even if people make use of these dustbins to dispose of garbage, these dustbins are rarely emptied. It is advisable to supply big polythene litter bags, instead of dustbins, which make the disposition of garbage easier. The water-logging in the locality has proved an ideal breeding place for mosquitoes. The need of the hour is to have regular visits of officials from your department to inspect the locality and to have meetings with the residents of the locality in order to make our locality a better and hygienic place to live in.

I hope you will personally supervise this situation and we hope to hear from you soon.

Yours sincerely
Abhishek

3. Srishti has been asked to write an information brochure for her classmates who plan an excursion to Fatehgarh in summer. She has made the following notes. Use these notes together with your own ideas and write the brochure.

What to see : Palaces, waterfalls, gardens Palaces galleries : Maharani’s Palace includes Wax Palace—540 AD—Whispering Sculptures—ancient rulers—limbs missing in a few. Waterfalls : Varsha—500 feet, stream on the outskirts Gardens : Rose gardens—Orchards—Vineyards

Answer:
This summer, as usual, we have planned an excursion for the class—a visit to FATEHGARH which is not only beautiful but also has a historical significance. Fatehgarh lies in the State of Uttar Pradesh. It is an eight-hour journey by bus; On reaching Fatehgarh we will be lounged in a Government Guest House. From there we shall proceed to visit the most famous place in Fatehgarh, the Maharani’s Palace, which includes the Wax Palace. It was built in 540 A.D. and it is known for its whispering galleries and the beautiful sculptures of ancient rulers. These sculptures are ancient, so it is not surprising that the limbs of a few rulers in some of these sculptures may be found missing. This palace is indeed one of the few examples of ancient Indian art and gives us a peep into the glorious and rich cultural art of ancient Indian history.

To cool you in the summers, we shall visit the Varsha waterfalls which fall from a height of 500 feet. It is a splendour to watch the water as it lashes down on to the ground and presents the most delightful sight. We also plan a visit to a stream which lies on the outskirts of Fatehgarh. Besides this, our excursion will include a visit to the beautiful rose gardens, fruit orchards and vineyards to view the flowers and the fruits in their full bloom. It promises to be an excursion which should not be missed and I can assure you that Our visit to Fatehgarh will be the most exciting and informative.

4. Sumit lives in a village. The entire village is worried about the degradation of Nila Lake in the village. He writes an article for publication in the local newspaper highlighting various factors responsible for the degradation of the lake. Use the information given below and write the article.

Construction of roads and bridges	Deforestation of catchment area	Illegal occupation	Pollution
1. Flooding	1. decrease in water level	1. blockage of canals	1. loss of water organisms
2. Disturbing the natural drainage	2. increase in the growth of weeds	2. flooding	2. fewer visiting birds
	3. shortage of drinking water	3. reduction cf fish

Answer:
I am being compelled to write this article to voice the concern of our entire village, Rampur, regarding the degradation of Nila Lake. This lake has been a part and parcel of our lives for numerous years and so it is very natural that our entire village is concerned about its degradation.

To provide an easy access to our village the construction of numerous roads and bridges has been taken up in recent years. Unfortunately, this has led to flooding almost every year during the rainy season and has also disturbed the natural drainage system. Due to deforestation of a large portion of the catchment area around the lake, the water level of the lake has decreased and there has been an increase in ’ the growth of weeds. There is also a considerable amount of reduction of fish in the lake. Illegal occupation of land around the lake has led to blockage of canals and shortage of drinking water. The lake water has become very polluted and there is a loss of water organisms. The number of migratory birds visiting the area has also decreased. So, it is indeed pathetic to see this slow but sure degeneration of Nila Lake which has been a major source of sustenance of our entire village.

We sincerely hope that after going through this article in your esteemed newspaper, concerned environmentalists will surely come forward to save Nila Lake from total degradation and effective measures will be taken up to improvise upon the present situation.

5. You are required to write an article for your school magazine on ‘Importance of Music in Life.’ Write it with the help of these notes in about 150-175 words.
Answer:
Music, be it vocal or instrumental, has indeed assumed a place of importance in , our complicated and hectic lives. It acts as a stimulant which activates our body ’ and mind. Music is also regarded as a fine art which attracts people of all age groups to pursue it not only as a hobby but also as a profession. A person endowed with musical capabilities regards this attribute as a natural gift which provides food for his soul. Some of the great musicians are held in very high esteem irrespective of the kind of music they propagate, whether Western, Oriental, Classical, Pop or Light. These musicians organise their concerts which attract people from all walks of life. These concerts can also be of great benefit to the children, who are interested in pursuing music as a hobby or career in their lives and receive musical training at the school level itself. By receiving training in music from a very young age, the basics of music will be instilled in a child and he will be able to relate to music very easily at a later stage in life. Therefore, each school should have the facilities needed .to give proper musical training to children. It is true that life these days is full of tensions and worries at every age. If there is no stimulating diversion in the form of music for a person, his life will become dismal and monotonous.

6. John writes a page of his diary recording his first experience of a public exami-nation. Below are listed his experiences. Write out a page of his diary.
Answer:
5th March, 20xx, 2 p.m.
On entering the examination hall/1 was appearing for my first public examination, the Science Olympiad, I had an extremely nervous feeling. The examination hall presented a rather dreary look. The only saving grace, in my opinion, Was a beautiful and enchanting portrait of Virgin Mary With Baby Jesus in her arms, hung inside the examination hall, to invoke a sense of confidence in the students and to remind us that we had the guidance and blessings of the Lord. I prayed to God fervently uncaring about the noise around me. The other students were rushing towards the examination hall and were busy in finding the correct seats in a hall that looked huge and overwhelmingly frightening. Once everyone had been seated, the examiner gave us some instructions regarding what we were required to do and what we were strictly prohibited from doing.

Then I received the Question Paper and I sat thoughtfully reading and reflecting on it. After I had giveh a thorough reading to the Question Paper, I began to answer it keeping in mind the fact that I had three hours to complete the paper. I managed to complete the paper fifteen minutes before the stipulated time and then began revising my paper. I spotted and corrected the few silly mistakes and errors that I had made and re-wrote some lines. After being totally satisfied with all that I had written, I finished my paper, took God’s name for yet another time and finally submitted it to the examiner.

Yours sincerely,
John

7. Gopal of 12, Raja Ki Mandi, Agra, wants to express his displeasure to the Newspaper Editor regarding the news that the bus stand near the railway station is being shifted to a new location. He feels that this would cause great hardship to the passengers. He made these notes for writing a letter to the Editor, The Times of India, New Delhi.Write that letter with the help of given notes.
Answer:
The Editor
The Times of India
New Delhi
19th December, 20xx ,
Subject: Regarding the news of bus stand near railway, station.

Sir,
Through the medium of this letter I wish to express my displeasure at the news that the bus stand, which is near the railway station, is being shifted to a new location. This will indeed be a cause of great hardship to the passengers who are commuting daily by bus and train. The present location of the bus stand is very convenient for the people who have to travel by train from their homes to their place of work. These daily commuters find it extremely easy to board a bus from the near by railway station where they disembark from the train. If the bus stand is shifted, the common « man will be forced to waste his time, energy, and money unnecessarily. Many shops have also come up in the vicinity of the bus stand. These shopkeepers will also lose their earnings if the bus stand is shifted because their regular customers are those people who commute daily by bus and the tourists who come to visit Agra in order to see one of the seven wonders of the world, The Taj Mahal. Even the commuters have An easy access to the market from where they can purchase the goods for their daily needs easily.

I suggest a solution to this problem. If the urgency is felt, it is advisable to add one more bus stand at a distance instead of shifting the present bus stand to a new location and causing a great deal of inconvenience to all.

Yours sincerely
Gopal

8. Special repairs are required in your rented house. You have to write a letter to your landlord asking him to undertake the repair work immediately. Take the help of these notes and write a letter in not more than 100-125 words. (M.P. Board 2014,16)
Answer:
A-394, XYZ Colony .
ABC Block
11th June, 20xx –

Dear Mr. Dev,
I had written to you earlier also to get some repair work done in your house, which you have rented me.

Now since the rainy season is at the onset, I reiterate my request to you to undertake this repair work immediately. The roof is leaking at various places and the wall’s ‘ plaster has also come off. Not only this, the floor has pot-holes, which cause a lot of inconvenience. The window panes of three windows are broken making the house an easy prey to the warm winds and dust from outside. The switches too are loose and there is a danger of short circuit. The premises also needs white-wash and paint on the doors and windows. The house is indeed in a pathetic and appalling state and requires urgent repairs. I am willing to share the cost of the repairs with . you. With your permission I can get the repairs done myself and the expenditure can be later deducted in the rent in monthly instalments.
I request you to give priority attention to this matter and hope to hear from you at \ the earliest.

Yours sincerely
ABC

9. You had sent a Money Order of ? 100 to M/s Subroto Publishing House, 36, Tagore Gardens, Kolkata as per the details given below. But it has not reached them till date. The details are: Money Order Registration No. 119 dated 2-l-20xx. Your address is 11, Teachers’ Colony, Naraingarh, (Punjab).
Write a letter of complaint to the Post Master in about 100-125 words.
Answer:
The Post Master
Naraingarh (Punjab)
31th January, 20xx

Subject: Complaint regarding delay of money order.

I would like to give in a written complaint regarding a misplaced Money Order that I had sent from your Post Office to Kolkata.

The Money Order Registration No. is 119 dated 2nd January 20xx. I had sent this Money Order of ₹100 to M/s Subroto Publishing House, 36, Tagore Gardens, Kolkata for a book that I needed urgently. On enquiring from them yesterday I found out that they had not dispatched the book because they have not received the required payment yet, whereas I have already sent ₹100 through a Money Order to them almost one month ago. Due to some negligence on the part of the Post Office Department, my Money Order has not yet reached them. I need the book urgently to prepare for my exams scheduled to start in the middle of March. So, it is my earnest request to you to look personally into the matter and make sure that my Money Order is received in Kolkata as soon as possible.

I hope you will ensure that my complaint is attended to at the earliest.

Thanking you.

Yours sincerely,
XYZ.

a sincere effort to keep our city clean, as a beautiful and clean city beckons the tourists.
By making these simple, but significant things possible, I am sure, tourism in our city can be improved.

Yours faithfully,
XYZ.

12. In an inter-school debate you have to speak in favour of the motion ‘Modem Gadgets have made us slaves tp machines’. Write a speech in favour of this motion,
Answer:
‘Modern Gadgets have made us slaves to machines’. Respected Principal, dear – teachers and my dear friends, today I am here to speak in favour of the topic ‘Modern Gadgets’ have made us slaves to machines’. I am endorsing the following points in favour of the given topic.

Modem gadgets have made us slaves to machines, without which it is as if our lives will undoubtedly come to a standstill. They have made the world jump forward with a leap, built up a glittering civilization, opened up innumerable avenues for the growth of knowledge, and added to the power of man to such an extent that it is possible to conceive that man could triumph over and shape his physical ! environment. Through the astonishing discoveries of these modern gadgets, man has been able to give a definite form to his imagination. It is indeed a fact that as a result of the invention of modern gadgets the tone and temper of life has changed beyond recognition. Through wireless telegraphs and fax machines messages can now be easily sent to any part of the world.

Modem gadgets incorporate all fhe comforts and highest standards in engineering innovation and reliability that have greatly contributed tp man’s welfare. New equipment for navigation, data-processing, computer-controlled radar system providing information on a variety of new products for use at construction sites are only some of the advantages of the modern gadgets. They have also greatly contributed’to our entertainment as radios, televisions, compact discs both audio and visual—are now no longer considered as luxury items but have assumed the status of being referred to as necessities. Indeed the advantages of these gadgets ate so many that they appear to have revolutionised every phase of life.

13. Anite johri of class X has just returned from a visit to Ooty which is in the grip of a severe water crisis. She finds that her hometown is also facing the same problem. She had picketl up th e following pamphlet from her hotel room and wants it tp be publicised.
WATER IS LIFE

	DOs	DON’ts
Washinghamd and face	Half fill basin-2 litres	Wash under running tap for 3- minutes-27 litres
Brushing teeth	Use a glass of water-reuse-1/2 litre	Let tap for 5 minutes-45 litres
Showering	Turn off tap before soaping, then rinse down-20 litres	Let tap run while soaping-90 litres
Bathing Leaky tap	Take a shower instead Get it repaired	Fill bath tub-110 litres Let it drip Slow drip-400 litres a day Fast drip-3000 litres a day

She decides to write a letter to the editor of the local newspaper highlighting ways and means of saving water.
Answer:
13, Baird Road
Pune, Maharashtra
The Editor
National Herald
Pune
11th June, 20xx ‘

Subject: Pamphlet publication regarding water crisis.

Sir,
I have returned from a visit to Ooty recently, which was in the grip of a severe water crisis. On returning to Pune, I found that the water problem is equally pathetic here. So, I would like to sugges* certain measures to save water. I had picked up a pamphlet from the hotel where I was staying at Ooty which highlighted the ways to save water and I want it to be publicised through your esteemed newspaper. Washing our hands and face under a running tap for only two minutes wastes about 27 litres of water whereas a half filled basin can do this work with only 2 litres of water. While brushing our teeth, if we let the tap run for five minutes, we waste 45 litres of water but if we use a glass of water, we consume only half a litre of water. If we turn off the tap while soaping our body before bathing, we use only f. 20 litres of water, whereas if we let it run we waste about 90 litres. We should avoid using bath-tubs as a filled bath tub wastes 110 litres of water. A leaky tap must be j repaired immediately because if the tap is allowed to leak slowly, it wastes 400 litres of water a day and a fast drip wastes 3,000 litres of water a day.

If each and every one of us understands it and decides to follow this simple but very important rule, we are sure to remedy our present water crisis to a great extent.

Yours sincerely
Anita Johri

14. Read the following extract from an article in a magazine and then using your own ideas as well, write an article for your school magazine on the Delights and Usefulness of Walking.
Answer:
The saying aptly goes, ‘A healthy body has a healthy mind’. So, it is imperative for each one of us to keep good health if we want our mind to be alert. In today’s hectic and busy life, it may, at times seem difficult to devote time for activities that keep us fit. This is where walking proves to be the most useful and easy activity.

Walking not only keeps our body healthy by the circulation of blood but also provides a delightful respite for us by the sheer delight it gitves. However, it is indeed a pity that some people who are most interested in walking refrain from it because in India walking is associated with deprivation and poverty. The false pride and wrong thinking then make them travel by car for even the shortest of distance. They would prefer to miss out on the delights of walking and prefer not to care about the good it would do to their health so as not to endanger their false prestige. It is high time that the educated lots of Indians put aside these petty notions and live their life for themselves and live it according to what they feel i s the best for them. Walking does not indicate deprivation and poverty and it is only the thinking of certain narrowminded people who have categorised the people walking or pedestrians as second class people.

Walking should be enjoyed as it gives pleasure and provides a wonderful opportunity for us to be in direct contact with nature, unlike at times the irksome ahd suffocating journey in a closed vehicle.

15. Read the following summary of a study conducted titled, ‘The Impact of Television Advertising on Children’. Write an article for the school magazine titled ‘Children and TV Advertising’.
Answer:

Children and TV Advertising

Television has become a very popular mode of entertainment which is unfortunately also making children more and more addicted to watching it. The television programmes pose to dominate their daily routine and many a time children do not even hesitate to ignore their studies because of their passion to stay glued to the television sets.

Almost seventy-five per cent of the children, who watch television most eagerly, are essentially interested in seeing various types of advertisements on the television. Children in the younger age group, below ten years of age, view the advertisements with more interest and enthusiasm than they watch any other programme on television. This is so because they see these advertisements as wonderful and short pictures with story lines and their inquisitive nature is so impatient that they can easily endure these short ad films with a lot of patience. These young children are totally taken in by the vibrant and glorious world shown in the various ad films. Also sometimes the content of an advertisement is not apt for children which further takes a toll their innocent minds.

It is only the older and mature children who understand that the ad films’ mere intention is to lure the consumer into buying their products by elevating their goods to a high scale where they appear most appealing and attractive. So, it is our moral responsibility to make sure that the young children’s innocent and ignorant minds are not impressed by what the ad films have to offer, but they view them solely for their entertainment.

16. Maria of 7, Gandhi Road, Jaipur, is very interested in sports and concerned about the state of sports in the country. She decides to write a letter to the editor of The Herald, Jaipur, on Why can’t we win an Olympic Gold? Write out the letter on her behalf.
Answer:
The Editor
The Herald
Jaipur
12th September, 20xx

Subject: Letter regarding India’s poor performance in Olympic Games.

Sir,
I write this letter to you as a concerned sports enthusiast to express my anguish at the poor state of sports in our country, as a result of which we have been unable to win only a gold medal in the Olympic Games held so far.

I feel that there is no sports culture in our country, in general, and so we are not able to nurture and groom the plenty of talent that our nation has. When the sportspersons of our country have to play and compete with international players in the World Olympics, their training and coaching should also match to that of their international counterparts, whereas in ctur country, the facilities for training and coaching are lacking and to a certain extent expenditure to enhance these fa cilities is sometimes considered as not necessary., We may fail to realize the importance of coaching centres in our day-to-day life but our inability to win a gold medal at the Olympic Games so far should make us realize the importance, of trainirig centres. It is also very unfortunate that the funds and sports scholarships available to budding sportspersons are very few. Political intervention at the time of selection also at times prevents the selectors in selecting the better players to play at the international level. Last but not the least, the public in general and the selectors and trainers in particular, do not seem to be affected by the lack of this’sports culture’in our country. Through your esteemed newspaper, I wish to appeal to the sports enthusiasts as well as people in general to boost up the sports culture in our country.

Yours sincerely
Maria

17. Vi jay witnessed an accident near theschool gate where a child fell down and was hurt quite badly. Many people were standing around but did not knoVift what to do. Finally, , someone who had a car quickly took him to hospital. However, Vijay felt that at least some of the students should have been able to render first-aid. He decided to write a letter to the editor about the importance of knowing first-aid. Using your own ideas write out Vijay’s letter in not more than 100-125 words.
Answer:
The Editor
News Week
17th October, 20xx

Subject: Indias regarding importance of knowing first-aid.

Sir,
Last week, I witnessed an accident near the school gate where a child fell down and hurt himself badly. The people standing around were unable to do anything except look on helplessly. It was at this moment that I realized the importance of knowing first-aid.

I feel that it is imperative for students specially and the people in general to at least ’ have the basic knowledge of rendering first-aid in case of an emergency. The use of first-aid often helps us to sustain a life till proper medical aid is available. The knowledge of first-aid will prove helpful not only in case of an accident but also to treat a burntictim, help a drowned casualty, and at times just to stop one from bleeding. The importance of first-aid should be instilled into the minds of children : at the school stage itself so that they do not panic in an accidental situation but cautiously and sensibly put their knowledge about rendering first-aid to the person who requires it into practice. Nothing is more precious to a person than his life and if timely use of first-aid can help someone till the time professional medical help is : available, it can prove to be the life-saving remedy.

Hence, everyone must have the knowledge of first-aid.

Yours sincerely
veerendra

18. Gaurav read the following in a newspaper article:
At the heart of the literacy campaign is the volunteer, who as instructor, resource person or local organiser, gives freely of her or bis time and puts in enormous effort to make the campaign succeed. He decided to speak at the school assembly on the experience of students who volunteer to take literacy classes. Write out his speech.
Answer:
Respected principal, dear teachers and my dear friends, today I wish speak on the problem of illiteracy in our country and the role of volunteers, organisers, who put their enormus efforts to eradicate this problem. You all are humbly advised to contribute your spare time to make this literacy mission a success.

Illiteracy is one of the major problems that confront our country. This problem assumes alarming proportions because of the democratic rule in our country. Democracy, which postulates enlightenment, is by and large a blessing, and illiteracy, which implies ignorance is therefore a curse.

To eradicate illiteracy to some extent, various students volunteer to take literacy classes and feel proud to help their unfortunate countrymen who have been deprived of the privilege of being educated. These voluntary workers, after receiving certain incentives and being provided with the requisite facilities ensure better results in the social arena. They have adopted new paths and motivated a large section of – masses towards their literacy classes. This voluntary service on the part of students has proven to be an effective measure for reaching out to the uneducated masses and thereby, further helped the illiterate persons to eradicate their constant exploitation and humiliation at the hands of society. The students have helped these people to become aware of the benefits of being literate/educated. They have also helped the illiterate people to move towards a positive change.

By undertaking this creditable but herculean task, these students feel a sense of pride in being able to make their contribution to take their country on the path of fast growth and progress.

19. You are required to speak on the subject ‘Pollution’ in the school morning assembly.
You may use ideas contained in the unit ‘Environment’. Write your speech.
Answer:
Environment
Environmental pollution is one of the major hazards that are threatening the ecological balance. The air that we inhale is polluted, the water we drink is contaminated and noise pollution has managed to take away the calmness and serenity from our otherwise hectic and tense lives. One of the main of pollution is the heavy and congested traffic which causes concentration of smoke and harmful particles in the atmosphere which is a permanent or chronic cause of various respiratory disorders. The incessant felling of trees, building of dams and the upcoming unplanned congested localities have disturbed the ecological balance to an alarmingly high level. To remedy this situation the urgent need of the hour is to plant as many trees wherever possible and to shift the factories and mills to places where their effect of pollution of the environment is minimum. To control traffic, car pools must be made so that the emission-levels from vehicular traffic can be reduced to the desired levels.

20. Write a letter to your friend inviting him to spend his vacation with you.
Answer:
56/4, Nehru Nagar,
New Delhi.
26th April, 20xx

Dear Ramesh,
Hope your examinations are over by now. What do you plan to do during the coming summer holidays? If you are hot going anywhere else, why don’t you come and . stay with us duringihese holidays? It shall indeed be of great fun. My Mummy and Daddy have been insisting me to invite you. Now, that you will be free, you must plan to visit Delhi. We shall move about and see various historical places in the capital. You would love to see the Red Fort, the Qutab Minar, Jama Masjid, and other places which attract numerous foreign tourists. You must be interested in watching these tall buildings. Don’t disappoint us this time. Do come down.

Your best friend,
Prakash

21. Write a letter to your father requesting him to allow you to go on an educational tour.
School Hostel
Govt. Boys Sr. Sec. School
Bhopal, Madhya Pradesh
8th May, 20xx

Respected Father,
I am fine here and hope you all to be well. You will be glad to know that I have done very well in the First Terminal Test which was held last week. I hope to get very good marks in all the subjects. Our school is organizing an educational tour to South India during the coming Autumn Break. Most of the students of my class are joining this tour. I, too, wish to join it. I am a student of history, so this tour will be of great practical advantage to me. This tour will be of about two weeks duration. We shall travel by a special railway boogie which is being reserved for us. Two senior teachers of the school will go with us on the tour. Each participant is to contribute ₹ 2,000 to meet the tour expenses.

With respect to mother and grandfather and love to Diplo.

Yours affectionately
Aakash

22. Write a letter to the Editor of a local daily complaining about loudspeakers’ nuisance in yoUr area.
E-49, Model Town
Bhopal
27th February, 20xx
The Editor
The Hindustan Times,
Bhopal.

Subject: Complaint regarding nuisance caused by loudspeakers.

Sir,
I shall feel grateful if you kindly publish the following few lines in the columns of your esteemed daily. I wish to draw the attention of the public through your daily about the nuisance of loudspeakers in the city. Loudspeakers have become great nuisance in the city of late. I wonder why some people do not bother about other’s convenience. They have no right to disturb our peace by constant noise made by loudspeakers. The Police – authorities appear to be silent about this nuisance. Not>ody can play loudspeakers after 10 pm but the loudspeakers fitted on the religious places continue to disturb the public throughout the night. In the interest of studies of- students, I pray to the public not to play loudspeakers at a high pitch during the night and early in the morning so that the students can prepare for their examinations well.

Yours faithfully
K.S. Bains.

MP Board Class 12th English Solutions

MP Board Class 12th Physics Solutions Chapter 5 चुम्बकत्व एवं द्रव्य

चुम्बकत्व एवं द्रव्य NCERT पाठ्यपुस्तक के अध्याय में पाठ्यनिहित प्रश्न एवं उनके उत्तर

प्रश्न 1.
भू-चुम्बकत्व सम्बन्धी निम्नलिखित प्रश्नों के उत्तर दीजिए
(a) एक सदिश को पूर्ण रूप से व्यक्त करने के लिए तीन राशियों की आवश्यकता होती है। उन तीन स्वतन्त्र राशियों के नाम लिखिए जो परम्परागत रूप से पृथ्वी के चुम्बकीय क्षेत्र को व्यक्त करने के लिए प्रयुक्त होती हैं।
(b) दक्षिण भारत में किसी स्थान पर नति कोण का मान लगभग 18° है। ब्रिटेन में आप इससे अधिक नति कोण की अपेक्षा करेंगे या कम की?
(c) यदि आप ऑस्ट्रेलिया के मेलबोर्न शहर में भू-चुम्बकीय क्षेत्र रेखाओं का नक्शा बनाएँ तो ये रेखाएँ पृथ्वी के अन्दर जाएँगी या इससे बाहर आएँगी?
(d) एक चुम्बकीय सुई जो ऊर्ध्वाधर तल में घूमने के लिए स्वतन्त्र है, यदि भू-चुम्बकीय उत्तर या दक्षिण ध्रुव पर रखी हो तो यह किस दिशा में संकेत करेगी?
(e) यह माना जाता है कि पृथ्वी का चुम्बकीय क्षेत्र लगभग एक चुम्बकीय द्विध्रुव के क्षेत्र जैसा है जो पृथ्वी के केन्द्र पर रखा है और जिसका द्विध्रुव आघूर्ण 8 × 10²²⁵ जूल टेस्ला^-1 है। कोई ढंग सुझाइए जिससे इस संख्या के परिमाण की कोटि जाँची जा सके।
(f) भूगर्भशास्त्रियों का मानना है कि मुख्य N-S चुम्बकीय ध्रुवों के अतिरिक्त, पृथ्वी की सतह पर कई अन्य स्थानीय ध्रुव भी हैं, जो विभिन्न दिशाओं में विन्यस्त हैं। ऐसा होना कैसे सम्भव है?
उत्तर :
(a) पृथ्वी के चुम्बकीय क्षेत्र को व्यक्त करने के लिए प्रयुक्त होने वाली तीन राशियाँ निम्नलिखित हैं-

• नति कोण अथवा नमन कोण δ
• दिक्पात का कोण θ
• पृथ्वी के चुम्बकीय क्षेत्र का क्षैतिज अवयव B_H

(b) चूँकि ब्रिटेन, दक्षिण भारत की तुलना में पृथ्वी के उत्तरी ध्रुव के अधिक समीप है, अतः यहाँ नति कोण अधिक होगा। वास्तव में ब्रिटेन में नति कोण लगभग 70° है।।
(c) ऑस्ट्रेलिया, पृथ्वी के दक्षिण गोलार्द्ध में स्थित है। चूंकि पृथ्वी के दक्षिण ध्रुव से चुम्बकीय क्षेत्र रेखाएँ बाहर निकलती हैं, अत: ये पृथ्वी से बाहर निकलती प्रतीत होंगी।
(d) चूँकि ध्रुवों पर पृथ्वी का चुम्बकीय क्षेत्र ऊर्ध्वाधर होता है, अतः ध्रुवों पर लटकी चुम्बकीय सुई (जो ऊर्ध्वाधर तल में घूमने के लिए स्वतन्त्र है) ऊर्ध्वाधर दिशा की ओर इंगित करेगी।

(e) यदि हम मान लें कि पृथ्वी के केन्द्र पर M चुम्बकीय-आघूर्ण का चुम्बकीय द्विध्रुव रखा है तो पृथ्वी के चुम्बकीय निरक्ष पर स्थित बिन्दुओं की इस द्विध्रुव के केन्द्र से दूरी पृथ्वी की त्रिज्या के बराबर होगी।
निरक्ष पर चुम्बकीय क्षेत्र \(B=\frac{\mu_{0}}{4 \pi} \cdot \frac{M}{r^{3}}\)
∴ \(M=\frac{4 \pi B r^{3}}{\mu_{0}} \)
प्रयोगों द्वारा पृथ्वी के चुम्बकीय निरक्ष पर B = 0.4 गॉस = 0.4 × 10^-4 टेस्ला तथा
r = R_E = 6.4 × 10⁶ मीटर

= 10.5 × 10²²
ऐम्पियर-मीटर 2 स्पष्ट है कि पृथ्वी के चुम्बकीय द्विध्रुव आघूर्ण का यह मान 8 × 10²² जूल टेस्ला^-1 के अत्यन्त निकट है। इस प्रकार पृथ्वी के चुम्बकीय द्विध्रुव आघूर्ण के परिमाण की कोटि की जाँच की जा सकती है।
(f) यद्यपि पृथ्वी का सम्पूर्ण चुम्बकीय क्षेत्र, एकल चुम्बकीय द्विध्रुव के कारण माना जाता है अपितु स्थानीय स्तर पर चुम्बकित पदार्थों के भण्डार अन्य चुम्बकीय ध्रुवों का निर्माण करते हैं।

प्रश्न 2.
निम्नलिखित प्रश्नों के उत्तर दीजिए –
(a) एक जगह से दूसरी जगह जाने पर पृथ्वी का चुम्बकीय क्षेत्र बदलता है। क्या यह समय के साथ भी
साथ भी बदलता है? यदि हाँ, तो कितने समय अन्तराल पर इसमें पर्याप्त परिवर्तन होते हैं?
(b) पृथ्वी के क्रोड में लोहा है, यह ज्ञात है। फिर भी भूगर्भशास्त्री इसको पृथ्वी के चुम्बकीय क्षेत्र का स्रोत नहीं मानते। क्यों?
(c) पृथ्वी के क्रोड के बाहरी चालक भाग में प्रवाहित होने वाली आवेश धाराएँ भू-चुम्बकीय क्षेत्र के लिए उत्तरदायी समझी जाती हैं। इन धाराओं को बनाए रखने वाली बैटरी (ऊर्जा स्रोत) क्या हो सकती है?
(d) अपने 4-5 अरब वर्षों के इतिहास में पृथ्वी अपने चुम्बकीय क्षेत्र की दिशा कई बार उलट चुकी होगी। भूगर्भशास्त्री, इतने सुदूर अतीत के पृथ्वी के चुम्बकीय क्षेत्र के बारे में कैसे जान पाते हैं?
(e) बहुत अधिक दरियों पर (30,000 किमी से अधिक) पृथ्वी का चुम्बकीय क्षेत्र अपनी द्विध्रुवीय आकृति से काफी भिन्न हो जाता है। कौन-से कारक इस विकृति के लिए उत्तरदायी हो सकते हैं?
(1) अन्तरातारकीय अन्तरिक्ष में 10^-12 टेस्ला की कोटि का बहुत ही क्षीण चुम्बकीय क्षेत्र होता है। क्या इस क्षीण चुम्बकीय क्षेत्र के भी कुछ प्रभावी परिणाम हो सकते हैं? समझाइए।
उत्तर :
(a) यद्यपि यह सत्य है कि पृथ्वी का चुम्बकीय क्षेत्र समय के साथ बदलता है, परन्तु चुम्बकीय-क्षेत्र में प्रेक्षण योग्य परिवर्तन के लिए कोई निश्चित समय सीमा निर्धारित नहीं की जा सकती। इसमें सैकड़ों वर्ष का समय भी लग सकता है।
(b) यह सुज्ञात तथ्य है कि पृथ्वी के क्रोड में पिघला हुआ लोहा है परन्तु इसका ताप लोहे के क्यूरी ताप से कहीं अधिक है। इतने उच्च ताप पर यह (लौहचुम्बकीय नहीं हो सकता) कोई चुम्बकीय क्षेत्र उत्पन्न नहीं कर सकता।
(c) यह माना जाता है कि पृथ्वी के गर्भ में उपस्थित रेडियोऐक्टिव पदार्थों के विघटन से प्राप्त ऊर्जा ही आवेश धाराओं की ऊर्जा का स्रोत है।

(d) प्रारम्भ में पृथ्वी के गर्भ में अनेकों पिघली हुई चट्टानें थीं जो समय के साथ धीरे-धीरे ठोस होती चली गईं। इन चट्टानों में मौजूद लौह-चुम्बकीय पदार्थ उस समय के पृथ्वी के चुम्बकीय क्षेत्र के अनुरूप संरेखित हो गए। इस प्रकार भूतकाल का पृथ्वी का चुम्बकीय क्षेत्र इन चट्टानों में चुम्बकीय पदार्थों के अनुरूपण में अभिलेखित है। इन चट्टानों का भूचुम्बकीय अध्ययन उस समय के पृथ्वी के चुम्बकीय क्षेत्र का ज्ञान प्रदान करता है।

(e) पृथ्वी के आयनमण्डल में अनेकों आवेशित कण विद्यमान रहते हैं जिनकी गति एक अलग चुम्बकीय क्षेत्र उत्पन्न करती है। यही चुम्बकीय क्षेत्र, पृथ्वी तल से अधिक दूरी पर पृथ्वी के चुम्बकीय क्षेत्र को विकृत कर देता है। आयनों के कारण उत्पन्न चुम्बकीय क्षेत्र सौर पवन पर निर्भर करता है।

(f) सूत्र R = \(\frac{m v}{q B}\) से, \(R \propto \frac{1}{B}\)
इससे स्पष्ट है कि अत्यन्त क्षीण चुम्बकीय क्षेत्र में गतिमान आवेशित कण अति विशाल त्रिज्या का मार्ग अपनाता है जो कि थोड़ी दूरी में लगभग सरल रेखीय प्रतीत होता है, अत: छोटी दूरियों के लिए सूक्ष्म चुम्बकीय क्षेत्र अप्रभावी प्रतीत होते हैं परन्तु बड़ी दूरियों में ये प्रभावी विक्षेपण उत्पन्न करते हैं।

प्रश्न 3.
एक छोटा छड़ चुम्बक जो एकसमान बाह्य चुम्बकीय क्षेत्र 0.25 टेस्ला के साथ 30° का कोण बनाता है, पर 4.5 × 10^-2 जूल का बल आघूर्ण लगता है। चुम्बक के चुम्बकीय-आघूर्ण का परिमाण क्या है?
हल :
दिया है : B= 0.25 टेस्ला, θ = 30°, r = 4.5 × 10^-2 जूल, M = ?
t= MB sin θ से,
\(M=\frac{\tau}{B \sin \theta}=\frac{4.5 \times 10^{-2}}{0.25 \times 0.5}\) (∵ sin 30° = 0.5)
∴ चुम्बकीय-आघूर्ण M = 0.36 जूल टेस्ला^-1।

प्रश्न 4.
चुम्बकीय-आघूर्ण m = 0.32 जूल टेस्ला^-1 वाला एक छोटा छड़ चुम्बक, 0.15 टेस्ला के एकसमान बाह्य चुम्बकीय क्षेत्र में रखा है। यदि यह छड़ क्षेत्र के तल में घूमने के लिए स्वतन्त्र हो तो क्षेत्र के किस विन्यास में यह (i) स्थायी सन्तुलन और (ii) अस्थायी सन्तुलन में होगा? प्रत्येक स्थिति में चुम्बक की स्थितिज ऊर्जा का मान बताइए।
हल :
दिया है : m = 0.32 जूल टेस्ला^-1
B= 0.15 टेस्ला ।
(i) जब चुम्बक का चुम्बकीय-आघूर्ण क्षेत्र की दिशा में संरेखित होगा तो चुम्बक स्थायी सन्तुलन की स्थिति में होगा।
इस स्थिति में स्थितिज ऊर्जा U₀ = – MB cos 0° [∵ U_θe = – MB cos θ]
= – 0.32 × 0.15 × 1
= – 0.048 जूल
या = 4.8×10^-2 जूल।

(ii) जब चुम्बकीय-आघूर्ण, क्षेत्र के विपरीत दिशा में संरेखित होगा (θ = 180°) तो चुम्बक अस्थायी सन्तुलन की स्थिति में होगा। इस स्थिति में स्थितिज ऊर्जा U_180° = – MB cos 180°
= – 0.32 × 0.15 × (-1)
= + 0.048 जूल
= 4.8 × 10^-2 जूल।

प्रश्न 5.
एक परिनालिका में पास-पास लपेटे गए 800 फेरे हैं तथा इसकी अनुप्रस्थ काट का क्षेत्रफल 2.5 × 10^-4 मीटर² है और इसमें 3.0 ऐम्पियर धारा प्रवाहित हो रही है। समझाइए कि किस अर्थ में यह परिनालिका एक छड़ चुम्बक की तरह व्यवहार करती है? इसके साथ जुड़ा हुआ चुम्बकीय-आघूर्ण कितना है?
हल :
दिया है : N = 800, i = 3.0 ऐम्पियर, A = 2.5 × 10^-4 मीटर²
∴ चुम्बकीय-आघूर्ण M = NiA = 800 × 3.0 × 2.5 × 10^-4
= 0.60 जूल टेस्ला^-1 ।
∵ परिनालिका को किसी चुम्बकीय क्षेत्र में लटकाने पर दण्ड चुम्बक के समान ही इस पर भी एक बल-युग्म कार्य करता है, अत: यह दण्ड-चुम्बक के समान व्यवहार करती है।

प्रश्न 6.
यदि प्रश्न 5 में बताई गई परिनालिका ऊर्ध्वाधर दिशा के परितः घूमने के लिए स्वतन्त्र हो और इस पर क्षैतिज दिशा में एक 0.25 टेस्ला का एकसमान चुम्बकीय क्षेत्र लगाया जाए, तो इस परिनालिका पर लगने वाले बल आघूर्ण का परिमाण उस समय क्या होगा, जब इसकी अक्ष आरोपित क्षेत्र की दिशा से 30° का कोण बना रही हो?
हल :
दिया है : B= 0.25 टेस्ला
पूर्व प्रश्न में,. M = 0.60 जूल टेस्ला^-1
θ = 30°
∴ परिनालिका पर बल-आघूर्ण t = MB sin θ = 0.60 × 0.25 × \(\frac { 1 }{ 2 }\)
= 0.075 जूल = 7.5 × 10^-2 जूल।

प्रश्न 7.
एक छड़ चुम्बक जिसका चुम्बकीय-आघूर्ण 1.5 जूल टेस्ला^-1 है, 0.22 टेस्ला के एक एकसमान चुम्बकीय क्षेत्र के अनुदिश रखा है।
(a) एक बाह्य बल आघूर्ण कितना कार्य करेगा यदि यह चुम्बक को चुम्बकीय क्षेत्र के (i) लम्बवत्, (ii) विपरीत दिशा में संरेखित करने के लिए घुमा दें।
(b) स्थिति (i) एवं (ii) में चुम्बक पर कितना बल आघूर्ण होता है?
हल :
दिया है : M = 1.5 जूल टेस्ला^-1,
B= 0.22 टेस्ला ।
(a) सूत्र W = – MB (cosθ₂ – cosθ₁) से,
(i) चुम्बक को θ₁ = 0° से θ₂ = 90° तक घुमाने में बल-आघूर्ण द्वारा कृत कार्य
W = – 1.5 × 0.22 [cos 90° – cos 0°]
= – 0.33 × (0- 1)= 0.33 जूल। (ii) चुम्बक को 01 = 0° से 02 = 180° तक घुमाने में बल आघूर्ण द्वारा कृत कार्य
W = – 1.5 × 0.22 [cos 180° – cos 0°]
= – 0.33 [ – 1 – 1] = 0.66 जूल।

(b) (i) स्थिति (i) में चुम्बक पर कार्यरत बल आघूर्ण
t= MB sin 90°
= 1.5 × 0.22 × 1 = 0.33 जूल।
(ii) स्थिति (ii) में चुम्बक पर कार्यरत बल-आघूर्ण
T= MB sin 180° = 0

प्रश्न 8.
एक परिनालिका जिसमें पास-पास 2000 फेरे लपेटे गए हैं तथा जिसके अनुप्रस्थ काट का क्षेत्रफल 1.6 × 10^-4 मीटर² है और जिसमें 4.0 ऐम्पियर की धारा प्रवाहित हो रही है, इसके केन्द्र से इस प्रकार लटकाई गई है कि यह एक क्षैतिज तल में घूम सके।
(a) परिनालिका के चुम्बकीय-आघूर्ण का मान क्या है?
(b) परिनालिका पर लगने वाला बल एवं बल आघूर्ण क्या है, यदि इस पर, इसकी अक्ष से 30° का कोण बनाता हुआ 7.5 × 10^-2 टेस्ला का एकसमान क्षैतिज चुम्बकीय क्षेत्र लगाया जाए?
हल :
दिया है : कुल फेरे
N = 2000,
A = 1.6 × 10^-4 मीटर²
i = 4.0 ऐम्पियर
B = 7.5 × 10^-2 टेस्ला

(a) परिनालिका का चुम्बकीय-आघूर्ण
M = NiA = 2000 × 4.0 × 1.6 × 10^-4
= 1.28 ऐम्पियर-मीटर²।

(b) सूत्र t = MB sin θ से,
अक्ष से θ = 30° के कोण पर लगे चुम्बकीय क्षेत्र के कारण बल आघूर्ण
t = 1.28 × 7.5 × 10^-2 × \(\frac { 1 }{ 2 }\)
= 4.8 × 10^-2 न्यूटन-मीटर
= 0.048 न्यूटन-मीटर। :: क्षेत्र एकसमान है, अत: परिनालिका पर कार्यरत बल शून्य होगा।

प्रश्न 9.
एक वृत्ताकार कुंडली जिसमें 16 फेरे हैं, जिसकी त्रिज्या 10 सेमी है और जिसमें 0.75 ऐम्पियर धारा प्रवाहित हो रही है, इस प्रकार रखी है कि इसका तल 5.0 × 10^-2 टेस्ला परिमाण वाले बाह्य क्षेत्र के लम्बवत् है। कुंडली, चुम्बकीय क्षेत्र के लम्बवत् और इसके अपने तल में स्थित एक अक्ष के चारों तरफ घूमने के लिए स्वतन्त्र है। यदि कुंडली को जरा-सा घुमा कर छोड़ दिया जाए तो यह अपनी स्थायी सन्तुलनावस्था के इधर-उधर 2.0 सेकण्ड-1 की आवृत्ति से दोलन करती है। कुंडली का अपने घूर्णन अक्ष के परितः जड़त्व-आघूर्ण क्या है?
हल :
दिया है : N = 16, r = 0.10 मीटर, i = 0.75 ऐम्पियर, B= 5.0 × 10^-2 टेस्ला
घूर्णन आवृत्ति γ = 2.0 सेकण्ड^-1, जड़त्व-आघूर्ण I = ?

कुंडली का चुम्बकीय-आघूर्ण
M = NiA = Ni × πr²
= 16 × 0.75 × 3.14 × (0.10)²
= 0.377 ऐम्पियर-मीटर²
∴ जड़त्व-आघूर्ण \(I=\frac{0.377 \times 5.0 \times 10^{-2}}{4 \times(3.14)^{2} \times(2.0)^{2}}\)
= 1.2 × 10^-4 किग्रा-मीटर।

प्रश्न 10.
एक चुम्बकीय सुई चुम्बकीय याम्योत्तर के समान्तर एक ऊर्ध्वाधर तल में घूमने के लिए स्वतन्त्र है। इसका उत्तरी ध्रुव क्षैतिज से 22° के कोण पर नीचे की ओर झुका है। इस स्थान पर चुम्बकीय क्षेत्र के क्षैतिज अवयव का मान 0.35 गाउस है। इस स्थान पर पृथ्वी के चुम्बकीय-क्षेत्र का परिमाण ज्ञात कीजिए।
हल :
दिया है : चुम्बकीय क्षेत्र का क्षैतिज अवयव
B_H = 0.35 गाउस
जबकि नति कोण δ = 22°
यदि पृथ्वी का सम्पूर्ण चुम्बकीय क्षेत्र B है तो B_H = B cos δ से,

\(B=\frac{B_{H}}{\cos \delta}=\frac{0.35}{\cos 22^{\circ}}\)
\(=\frac{0.35}{0.9272}\) = 0.38 गाउस।

प्रश्न 11.
दक्षिण अफ्रीका में किसी स्थान पर एक चुम्बकीय सुई भौगोलिक उत्तर से 12° पश्चिम की ओर संकेत करती है। चुम्बकीय याम्योत्तर में संरेखित नति-वृत्त की चुम्बकीय सुई का उत्तरी ध्रुव क्षैतिज से 60° उत्तर की
ओर संकेत करता है। पृथ्वी के चुम्बकीय क्षेत्र का क्षैतिज अवयव मापने पर 0.16 गाउस पाया जाता है। इस स्थान पर पृथ्वी के क्षेत्र का परिमाण और दिशा बताइए।
हल :
दिया है : नति कोण 6 = 60° जबकि दिक्पात का कोण θ = 12° उत्तर से पश्चिम की ओर B_H = 0.16 गाउस
B_H = B cos δ से,
\(B=\frac{B_{H}}{\cos \delta}=\frac{0.16}{\cos 60^{\circ}}\)
\(=\frac{0.16}{0.5}\) = 0.32 गाउस
अत: इस स्थान पर पृथ्वी का सम्पूर्ण क्षेत्र 0.32 गाउस है जिसकी दिशा भौगोलिक याम्योत्तर से 12° पश्चिम की ओर क्षैतिज से 60° के कोण पर ऊपर की ओर है।

प्रश्न 12.
किसी छोटे छड़ चुम्बक का चुम्बकीय-आघूर्ण 0.48 जूल टेस्ला^-1 है। चुम्बक के केन्द्र से 10 सेमी की दूरी पर स्थित किसी बिन्दु पर इसके चुम्बकीय क्षेत्र का परिमाण एवं दिशा बताइए यदि यह बिन्दु (i) चुम्बक के अक्ष पर स्थित हो, (ii) चुम्बक के अभिलम्ब समद्विभाजक पर स्थित हो।
हल :
दिया है : M = 0.48 जूल टेस्ला^-1, r = 0.10 मीटर, B= ?
(i) जब बिन्दु चुम्बक के अक्ष पर है तब चुम्बकीय क्षेत्र

= 0.96 × 10^-4 टेस्ला ।
अथवा B_ax = 0.96 गाउस दक्षिणी ध्रुव से उत्तरी ध्रुव की ओर
(ii) जब बिन्दु चुम्बक के लम्ब समद्विभाजक पर है तो चुम्बकीय क्षेत्र
B_eq= \(\frac { 1 }{ 2 }\)B_ax = \(\frac { 1 }{ 2 }\) × 0.96
= 0.48 गाउस ( उत्तरी ध्रुव से दक्षिणी ध्रुव की ओर)।

प्रश्न 13.
क्षैतिज तल में रखे एक छोटे छड़ चुम्बक का अक्ष, चुम्बकीय उत्तर-दक्षिण दिशा के अनुदिश है। सन्तुलन बिन्दु चुम्बक के अक्ष पर, इसके केन्द्र से 14 सेमी दूर स्थित है। इस स्थान पर पृथ्वी का चुम्बकीय क्षेत्र 0.36 गाउस एवं नति कोण शून्य है। चुम्बक के अभिलम्ब समद्विभाजक पर इसके केन्द्र से उतनी ही दूर (14 सेमी) स्थित किसी बिन्दु पर परिणामी चुम्बकीय क्षेत्र क्या होगा?
हल :
दिया है : पृथ्वी का चुम्बकीय क्षेत्र B= 0.36 गाउस, नति कोण δ = 0°

अक्ष पर सन्तुलन बिन्दु की दूरी r = 0.14 मीटर
माना सन्तुलन बिन्दु पर चुम्बक के कारण चुम्बकीय क्षेत्र B_ax है
तब सन्तुलन की अवस्था में ,
B_ax = B_H⇒ B_ax = B cos δ = B
ये क्षेत्र परस्पर विपरीत होंगे।
अभिलम्ब समद्विभाजक पर, इतनी ही दूरी पर चुम्बक के कारण चुम्बकीय क्षेत्र
B_eq = \(\frac { 1 }{ 2 }\)B_ax⇒ B_eq= \(\frac { 1 }{ 2 }\)B
परन्तु यहाँ पृथ्वी का क्षेत्र B_H = B तथा चुम्बक का क्षेत्र दोनों एक ही दिशा में हैं, अतः यहाँ परिणामी क्षेत्र
B₁ = B_eq + B = \(\frac { 1 }{ 2 }\)B + B
= \(\frac { 3 }{ 2 }\)B = \(\frac { 3 }{ 2 }\) × 0.36 = 0.54 गाउस।
इसकी दिशा पृथ्वी के क्षेत्र के अनुदिश होगी।

प्रश्न 14.
यदि प्रश्न 13 में वर्णित चुम्बक को 180° से घुमा दिया जाए तो सन्तुलन बिन्दुओं की नई स्थिति क्या होगी?
हल :
इस स्थिति में, सन्तुलन बिन्दु अभिलम्ब समद्विभाजक पर प्राप्त होगा।
अक्षीय स्थिति में सन्तुलन बिन्दु हेतु

अन्तिम स्थिति में, प्रश्न के अनुसार r_ax = 0.14 मीटर
r_eq = \(\frac{0.14}{(2)^{1 / 3}}\) × 2^-1/3
= 0.111 मीटर = 11.1 सेमी।
अत: सन्तुलन बिन्दु निरक्षीय स्थिति में केन्द्र से 11.1 सेमी की दूरी पर मिलेगा।

प्रश्न 15.
एक छोटा छड़ चुम्बक जिसका चुम्बकीय-आघूर्ण 5.25 × 10^-2 जूल टेस्ला^-1 है, इस प्रकार रखा है कि इसका अक्ष पृथ्वी के क्षेत्र की दिशा के लम्बवत् है। चुम्बक के केन्द्र से कितनी दूरी पर, परिणामी क्षेत्र पृथ्वी के क्षेत्र की दिशा से 45° का कोण बनाएगा, यदि हम (a) अभिलम्ब समद्विभाजक पर देखें, (b) अक्ष पर देखें? इस स्थान पर पृथ्वी के चुम्बकीय क्षेत्र का परिमाण 0.42 गाउस है। प्रयुक्त दूरियों की तुलना में चुम्बक की लम्बाई की उपेक्षा कर सकते हैं।
हल :
दिया है : M = 5.25 × 10^-2जूल टेस्ला^-1
पृथ्वी का क्षेत्र B_H = 0.42 गाउस
(a) माना ऐसा, चुम्बक के निरक्ष पर उसके केन्द्र से r_eq दूरी पर होता है।
इस बिन्दु पर चुम्बक के कारण क्षेत्र

प्रश्न 16.
निम्नलिखित प्रश्नों के उत्तर दीजिए –
(a) ठण्डा करने पर किसी अनुचुम्बकीय पदार्थ का नमूना अधिक चुम्बकन क्यों प्रदर्शित करता है? ( एक ही चुम्बककारी क्षेत्र के लिए)
(b) अनुचुम्बकत्व के विपरीत, प्रतिचुम्बकत्व पर ताप का प्रभाव लगभग नहीं होता। क्यों?
(c) यदि एक टोरॉइड में बिस्मथ का क्रोड लगाया जाए तो इसके अन्दर चुम्बकीय क्षेत्र उस स्थिति की तुलना में (किंचित) कम होगा या (किंचित) ज्यादा होगा, जबकि क्रोड खाली हो?
(d) क्या किसी लौहचुम्बकीय पदार्थ की चुम्बकशीलता चुम्बकीय क्षेत्र पर निर्भर करती है? यदि हाँ, तो उच्च चुम्बकीय क्षेत्रों के लिए इसका मान कम होगा या अधिक? . (e) किसी लौह चुम्बक की सतह के प्रत्येक बिन्दु पर चुम्बकीय क्षेत्र रेखाएँ सदैव लम्बवत् होती हैं [यह तथ्य उन स्थिरविद्युत क्षेत्र रेखाओं के सदृश है जो कि चालक की सतह.के प्रत्येक बिन्दु पर लम्बवत् होती हैं। क्यों?
(f) क्या किसी अनुचुम्बकीय नमूने का अधिकतम सम्भव चुम्बकन, लौहचुम्बक के चुम्बकन के परिमाण की कोटि का होगा?
उत्तर :
(a) ताप के घटने पर पदार्थ के परमाण्वीय चुम्बकों का ऊष्मीय विक्षोभ कम हो जाता है जिसके कारण इन चुम्बकों के बाह्य चुम्बकीय क्षेत्र की दिशा में संरेखित होने की प्रवृत्ति बढ़ जाती है। –
(b) प्रतिचुम्बकीय पदार्थ के परमाणु ऊष्मीय विक्षोभ के कारण, भले ही किसी भी स्थिति में हों, उनमें बाह्य
चुम्बकीय क्षेत्र के कारण, प्रेरित चुम्बकीय-आघूर्ण सदैव ही बाह्य क्षेत्र के विपरीत दिशा में प्रेरित होता है। इस प्रकार प्रतिचुम्बकत्व पर ताप का कोई प्रभाव नहीं होता।
(c) चूँकि बिस्मथ एक प्रतिचुम्बकीय पदार्थ है, अत: चुम्बकीय क्षेत्र अपेक्षाकृत कुछ कम हो जाएगा।
(d) लौहचुम्बकीय पदार्थों की चुम्बकशीलता बाह्य चुम्बकीय क्षेत्र पर निर्भर करती है तथा तीव्र चुम्बकीय, क्षेत्र के लिए इसका मान कम होता है।
(e) जब दो माध्यम किसी स्थान पर मिलते हैं जिनमें से एक के लिए µ >>1 हो तो इनके सीमा पृष्ठ पर क्षेत्र रेखाएँ लम्बवत् हो जाती हैं।
(1) हाँ, किसी अनुचुम्बकीय पदार्थ का अधिकतम सम्भव चुम्बकत्व, लौहचुम्बकीय पदार्थ के चुम्बकन के परिमाण की कोटि का हो सकता है। परन्तु किसी अनुचुम्बकीय पदार्थ को इस कोटि तक चुम्बकित करने के लिए अति उच्च चुम्बकीय क्षेत्र की आवश्यकता होती है जिसे प्राप्त करना व्यवहार में सम्भव नहीं है।

प्रश्न 17.
निम्नलिखित प्रश्नों के उत्तर दीजिए –
(a) लौहचुम्बकीय पदार्थ के चुम्बकन वक्र की अनुत्क्रमणीयता, डोमेनों के आधार पर गुणात्मक दृष्टिकोण से समझाइए।
(b) नर्म लोहे के एक टुकड़े के शैथिल्य लूप का क्षेत्रफल, कार्बन-स्टील के टुकड़े के शैथिल्य लप के क्षेत्रफल से कम होता है। यदि पदार्थ को बार-बार चुम्बकन चक्र से गुजारा जाए तो कौन-सा टुकड़ा अधिक ऊष्मा ऊर्जा का क्षय करेगार
(c) लौह चुम्बक जैसा शैथिल्य लूप प्रदर्शित करने वाली कोई प्रणाली स्मृति संग्रहण की युक्ति है। इस कथन की व्याख्या कीजिए।
(d) कैसेट के.चुम्बकीय फीतों पर परत चढ़ाने के लिए या आधुनिक कम्प्यूटर में स्मृति संग्रहण के लिए, किस तरह के लौहचुम्बकीय पदार्थों का इस्तेमाल होता है? ।
(e) किसी स्थान को चुम्बकीय क्षेत्र से परिरक्षित करना है। कोई विधि सुझाइए।
उत्तर :
(a) जब बाह्य चुम्बकीय क्षेत्र को शून्य कर दिया जाता है तो भी लौहचुम्बकीय पदार्थ के डोमेन अपनी प्रारम्भिक स्थिति में नहीं लौट पाते अपितु उनमें कुछ चुम्बकन शेष रह जाता है। यही कारण है कि लौहचुम्बकीय पदार्थों का चुम्बकन वक्र अनुत्क्रमणीय होता है।
(b) किसी पदार्थ के शैथिल्य लूप का क्षेत्रफल एक पूर्ण चुम्बकन चक्र में होने वाली ऊर्जा-हानि को प्रदर्शित करता है। यह ऊर्जा-हानि ही पदार्थ में ऊष्मा के रूप में उत्पन्न होती है। चूंकि कार्बन-स्टील के शैथिल्य लूप का क्षेत्रफल अधिक है, अत: इसमें अधिक ऊष्मा उत्पन्न होगी अर्थात् कार्बन-स्टील का टुकड़ा अधिक ऊष्मा क्षय करेगा।
(c) किसी लौहचुम्बकीय पदार्थ का चुम्बकन उस पर लगाए गए बाह्य चुम्बकीय-क्षेत्र के चक्रों की संख्या पर निर्भर करता है। इस प्रकार किसी लौह चुम्बकीय पदार्थ का चुम्बकन उस पर लगाए गए चुम्बकन चक्र की सूचना दे सकता है। इस प्रकार चुम्बकन चक्र की स्मृति, चुम्बकित पदार्थ के नमूने में एकत्र हो जाती है।
(d) इस कार्य के लिए सिरेमिक पदार्थों का प्रयोग किया जाता है।
(e) किसी स्थान को चुम्बकीय क्षेत्र से परिरक्षित करने के लिए उस स्थान को नर्म लोहे के रिंग से घेर देना चाहिए। इससे चुम्बकीय क्षेत्र रेखाएँ, नर्म लोहे के रिंग से होकर गुजर जाती हैं तथा रिंग के भीतर प्रवेश नहीं कर पातीं।

प्रश्न 18.
एक लम्बे, सीधे, क्षैतिज केबल में 2.5 ऐम्पियर धारा, 10° दक्षिण-पश्चिम से 10° उत्तर-पूर्व की ओर प्रवाहित हो रही है। इस स्थान पर चुम्बकीय याम्योत्तर भौगोलिक याम्योत्तर के 10° पश्चिम में है। यहाँ पृथ्वी का चुम्बकीय क्षेत्र 0.33 गाउस एवं नति कोण शून्य है। उदासीन बिन्दुओं की रेखा निर्धारित कीजिए। (केबल की मोटाई की उपेक्षा कर सकते हैं।)
(उदासीन बिन्दुओं पर, धारावाही केबल द्वारा चुम्बकीय क्षेत्र, पृथ्वी के क्षैतिज घटक के चुम्बकीय क्षेत्र के समान एवं विपरीत दिशा में होता है।)
हल :
दिया है : पृथ्वी का क्षेत्र B= 0.33 × 10^-4 टेस्ला, नति कोण δ = 0°
∴ पृथ्वी के क्षेत्र का क्षैतिज घटक B_H = B cos δ = 0.33 × 10^-4 टेस्ला
माना उदासीन बिन्दु तार से a दूरी पर है, तब

इस प्रकार, उदासीन बिन्दु रेखा केबल के समान्तर ऊपर की ओर केबल से 1.5 सेमी की दूरी पर होगी।

प्रश्न 19.
किसी स्थान पर एक टेलीफोन केबल में चार लम्बे, सीधे, क्षैतिज तार हैं जिनमें से प्रत्येक में 1.0 ऐम्पियर की धारा पूर्व से पश्चिम की ओर प्रवाहित हो रही है। इस स्थान पर पृथ्वी का चुम्बकीय क्षेत्र 0.39 गाउस एवं नति कोण 35° है। दिक्पात कोण लगभग शून्य है। केबल के 4.0 सेमी नीचे और 4.0 सेमी ऊपर परिणामी चुम्बकीय क्षेत्रों के मान क्या होंगे?
हल :
पृथ्वी का चुम्बकीय क्षेत्र
B = 0.39 × 10^-4 टेस्ला, δ = 35°, i= 1.0 ऐम्पियर
पृथ्वी के क्षेत्र का क्षैतिज अवयव
B_H = B cos δ = 0.39 × cos 35°
= 0.39 × 0.819
= 0.319 गाउस (दक्षिण से उत्तर)
तथा ऊर्ध्वाधर अवयव
B_V = B sin δ = 0.39 × sin 35° = 0.39 × 0.573
= 0.224 गाउस
चार केबलों के कारण उनसे a = 4.0x 10^-2 मीटर की दूरी पर चुम्बकीय क्षेत्र

= 0.2 × 10^-4 टेस्ला = 0.2 गाउस
केबल के ऊपर चुम्बकीय क्षेत्र B’ क्षैतिजतः दक्षिण से उत्तर की ओर तथा केबल के नीचे यह क्षेत्र क्षैतिजतः उत्तर से दक्षिण की ओर होगा।
केबल के नीचे चुम्बकीय क्षेत्र
यहाँ B_H व B’ परस्पर विपरीत हैं।
∴ क्षैतिज अवयव

अत: केबल के नीचे नेट चुम्बकीय क्षेत्र 0.254 गाउस है जो क्षैतिज से 62° के कोण पर है।
केबल के ऊपर चुम्बकीय क्षेत्र
यहाँ B_H व B’ एक ही दिशा में हैं।
∴ क्षैतिज अवयव
B’_H = B_H + B’ = 0.319 + 0.2 = 0.519 गाउस
जबकि B_V = 0.224 गाउस

अत: नेट चुम्बकीय क्षेत्र 0.57 गाउस है जो क्षैतिज से 23° के कोण पर है।

प्रश्न 20.
एक चुम्बकीय सुई जो क्षैतिज तल में घूमने के लिए स्वतन्त्र है, 30 फेरों एवं 12 सेमी त्रिज्या वाली एक कुंडली के केन्द्र पर रखी है। कुंडली एक ऊर्ध्वाधर तल में है और चुम्बकीय याम्योत्तर से 45° का कोण बनाती है। जब कुंडली में 0.35 ऐम्पियर धारा प्रवाहित होती है, चुम्बकीय सुई पश्चिम से पूर्व की ओर संकेत करती है।
(a) इस स्थान पर पृथ्वी के चुम्बकीय क्षेत्र के क्षैतिज अवयव का मान ज्ञात कीजिए।
(b) कुंडली में धारा की दिशा उलट दी जाती है और इसको अपनी ऊर्ध्वाधर अक्ष पर वामावर्त दिशा में (ऊपर से देखने पर ) 90° के कोण पर घुमा दिया जाता है। चुम्बकीय सुई किस दिशा में ठहरेगी? इस स्थान पर चुम्बकीय दिक्पात शून्य लीजिए।
हल :
(a) दिया है : कुंडली में फेरों की संख्या N = 30
धारा i = 0.35 ऐम्पियर, त्रिज्या a = 0.12 मीटर
कंडली के केन्द्र पर चम्बकीय क्षेत्र \(B=\frac{\mu_{0} N i}{2 a}=\frac{4 \pi \times 10^{-7} \times 30 \times 0.35}{2 \times 0.12}\)
= 0.55 गाउस
यह क्षेत्र कुंडली के तल के लम्बवत् है।
∵ चुम्बकीय सुई पूर्व-पश्चिम दिशा में ठहरती है, अतः इस स्थान पर नेट चुम्बकीय क्षेत्र पूर्व पश्चिम दिशा में होगा।
यह तभी सम्भव है जबकि क्षेत्र B का उत्तर-दक्षिण दिशा में अवयव B_H को सन्तुलित कर ले।
अर्थात् B_H = B cos 45° = 0.55 × \(\frac{1}{\sqrt{2}}\)
पृथ्वी के क्षेत्र का क्षैतिज अवयव B_H = 0.39 गाउस।

(b) चित्र-5.4 (b) से स्पष्ट है कि इस बार नेट चुम्बकीय क्षेत्र पूर्व से पश्चिम की ओर होगा। अतः चुम्बकीय सुई पूर्व से पश्चिम की ओर संकेत करेगी।

प्रश्न 21.
एक चुम्बकीय द्विध्रुव दो चुम्बकीय क्षेत्रों के प्रभाव में है। ये क्षेत्र एक-दूसरे से 60° का कोण बनाते हैं और उनमें से एक क्षेत्र का परिमाण 1.2 × 10^-2 टेस्ला है। यदि द्विध्रुव स्थायी सन्तुलन में इस क्षेत्र से 15° का कोण बनाए, तो दूसरे क्षेत्र का परिमाण क्या होगा?
हल :
दिया है : B₁ = 1.2 × 10^-2 टेस्ला, B₂ = ?
∵ द्विध्रुव एक क्षेत्र से 15° का कोण बनाता है, अत: दूसरे क्षेत्र से 45° का कोण बनाएगा।
सन्तुलन की स्थिति में दोनों के कारण द्विध्रुव पर कार्यरत बल-युग्म के आघूर्ण परस्पर सन्तुलित हो जाएँगे।

∴ MB₁ sin 15o = MB₂ sin 45°
B₂= \(\frac{B_{1} \sin 15^{\circ}}{\sin 45^{\circ}}\)
= \(\frac{1.2 \times 10^{-2} \times 0.2588}{0.707}\)
450
150
= 4.39 × 10^-3 टेस्ला
= 4.4 x 10^-3 टेस्ला ।

प्रश्न 22.
एक समोर्जी 18 किलो इलेक्ट्रॉन-वोल्ट वाले इलेक्ट्रॉनों के किरण पुंज पर जो शुरू में क्षैतिज दिशा में गतिमान हैं, 0.04 गाउस का एक क्षैतिज चुम्बकीय क्षेत्र, जो किरण पुंज की प्रारम्भिक दिशा के लम्बवत् है, लगाया गया है। आकलन कीजिए 30 सेमी की क्षैतिज दूरी चलने में किरण पुंज कितनी दूरी ऊपर या नीचे विस्थापित होगा? (me = 9.11 × 10^-31 किग्रा, e= 1.60 × 10^-19 कूलॉम)।
[नोट : इस प्रश्न में आँकड़े इस प्रकार चुने गए हैं कि उत्तर से आपको यह अनुमान हो कि T.V. सेट में इलेक्ट्रॉन गन से पर्दे तक इलेक्ट्रॉन किरण पुंज की गति भू-चुम्बकीय क्षेत्र से किस प्रकार प्रभावित होती है।
हल :
दिया है : B= 0.04 गाउस = 4 x 10^-6 टेस्ला ।

माना इलेक्ट्रॉनों का वेग υ _x है, तब \(\frac { 1 }{ 2 }\)m_eυ _x² = K ⇒ υ _x = \(\sqrt{\frac{2 K}{m_{e}}}[latex]
इलेक्ट्रॉन, चुम्बकीय क्षेत्र के कारण वृत्तीय मार्ग पर गति करते हैं जिसकी त्रिज्या । निम्नलिखित है –

माना इलेक्ट्रॉन-पुंज बिन्दु A पर चुम्बकीय क्षेत्र में क्षैतिज दिशा में प्रवेश करते हैं तथा क्षैतिज दिशा में x = 0.30 मीटर दूरी तय करने तक बिन्दु B पर पहुँच जाते हैं, तब (चित्र से),
sin θ = [latex]\frac{x}{R}=\frac{0.30}{11.3}\)= 0.0265
θ = sin^-1(0.0265) = 1.52°
∴ इलेक्ट्रॉनों का ऊपर अथवा नीचे की ओर विस्थापन
y= OA – OC = R – R cos θ = R (1 – cosθ) = 11.3 (1 – 0.9996)
= 4.0 × 10^-3 मीटर अथवा
y = 4 मिमी।

प्रश्न 23.
अनुचुम्बकीय लवण के एक नमूने में 2.0 × 10²⁴ परमाणु द्विध्रुव हैं जिनमें से प्रत्येक का द्विध्रुव आघूर्ण 1.5 × 10^-23 जूल टेस्ला^-1 है। इस नमूने को 0.64 टेस्ला के एक एकसमान चुम्बकीय क्षेत्र में रखा गया है और 4.2 K ताप तक ठण्डा किया गया। इसमें 15% चुम्बकीय संतृप्तता आ गई। यदि इस नमूने को 0.98 टेस्ला के चुम्बकीय क्षेत्र में 2.8 K ताप पर रखा हो तो इसका कुल द्विध्रुव आघूर्ण कितना होगा? (यह मान सकते हैं कि क्यूरी नियम लागू होता है।)
हल :
दिया है : N = 2.0 × 10²⁴, m = 1.5 × 10^-23 जूल टेस्ला -1, B₁ = 0.64 टेस्ला, T₁= 4.2 K, चुम्बकीय संतृप्तता M₁ = 15%, B₂ = 0.98 टेस्ला, T₂ = 2.8 K,
चुम्बकीय संतृप्तता M₂ = ?
चुम्बकीय संतृप्तता की स्थिति में,
पदार्थ का चुम्बकीय-आघूर्ण M = Nm = 2.0 × 10²⁴ × 1.5 × 10^-23 = 30 जूल टेस्ला^-1
प्रथम स्थिति में,
चम्बकीय-आघूर्ण M₁ = M का 15% = \(\frac{15 M}{100}=\frac{15 \times 30}{100}\) = 4.5 जल टेस्ला^-1
∵ क्यूरी नियम लागू होता है। अतः

प्रश्न 24.
एक रोलैंड रिंग की औसत त्रिज्या 15 सेमी है और इसमें 800 आपेक्षिक चुम्बकशीलता के लौह चुम्बकीय क्रोड पर 3500 फेरे लिपटे हुए हैं। 1.2 ऐम्पियर की चुम्बककारी धारा के कारण इसके क्रोड में कितना घुम्बकीय क्षेत्र (\(\overrightarrow{\mathbf{B}}\)) होगा?
हल :
दिया है : औसत त्रिज्या a = 0.15 मीटर, μ_r = 800, N = 3500, i = 1.2 ऐम्पियर, B= ?

प्रश्न 25.
किसी इलेक्ट्रॉन के नैज चक्रणी कोणीय संवेग \(\overrightarrow{\mathbf{s}}\) एवं कक्षीय कोणीय संवेग \(\overrightarrow{1}\) के साथ जुड़े चुम्बकीय-आघूर्ण क्रमशः \(\overrightarrow{\mu_{\mathrm{S}}}\) और \(\overrightarrow{\mu_{1}}\) हैं। क्वाण्टम सिद्धान्त के आधार पर (और प्रयोगात्मक रूप से अत्यन्त परिशुद्धतापूर्वक पुष्ट) इनके मान क्रमशः निम्न प्रकार दिए जाते हैं –
μ_s = – \(\left(\frac{e}{2 m}\right) \overrightarrow{\mathrm{i}}\) एवं μ_l= – \left(\frac{e}{2 m}\right) \overrightarrow{\mathbf{1}}
इनमें से कौन-सा व्यंजक चिरसम्मत सिद्धान्तों के आधार पर प्राप्त करने की आशा की जा सकती है? उस चिरसम्मत आधार पर प्राप्त होने वाले व्यंजक को व्युत्पन्न कीजिए।
हल :
व्यंजक \(\vec{\mu}_{1}=-\left(\frac{e}{2 m}\right) \overrightarrow{1}\), चिरसम्मत सिद्धान्तों के आधार पर प्राप्त किया जा सकता है।
माना इलेक्ट्रॉन r त्रिज्या की वृत्तीय कक्षा में चक्कर लगा रहा है तथा इसका परिक्रमण काल T है, तब
परिक्रमण के कारण कक्षा में धारा i = \(\frac{e}{T}\)
∴ परिक्रमण के कारण उत्पन्न चुम्बकीय-आघूर्ण का परिमाण

जबकि कक्षा में घूमते इलेक्ट्रॉन का कोणीय संवेग

∵ इलेक्ट्रॉन का आवेश e ऋणात्मक है, अतः \(\vec{\mu}_{1} व \overrightarrow{1}\) सदिशों की दिशाएँ परस्पर विपरीत होंगी। . :
∴ सदिश रूप में लिखने पर, = \(\overrightarrow{\mu_{1}}=-\left(\frac{e}{2 m}\right) \overrightarrow{1}\)

चुम्बकत्व एवं द्रव्य NCERT भौतिक विज्ञान प्रश्न प्रदर्शिका (Physics Exemplar LO Problems) पुस्तक से चयनित महत्त्वपूर्ण प्रश्नों के हल

चुम्बकत्व एवं द्रव्य बहुविकल्पीय प्रश्नोत्तर

प्रश्न 1.
पृथ्वी के चुम्बकीय क्षेत्र को पृथ्वी के केन्द्र पर स्थित बिन्दु द्विध्रुव के क्षेत्र का प्रतिरूप माना जा सकता है। इस द्विध्रुव का अक्ष पृथ्वी के अक्ष से 11.3° का कोण बनाता है। मुम्बई में द्विक्पात लगभग शून्य है, तब –
(a) पृथ्वी पर दिक्पात का मान 11.3° पश्चिम से 11.3° पूर्व के बीच परिवर्तित होता है।
(b) निम्नतम दिक्पात शून्य अंश (0°) है।
(c) द्विध्रुव अक्ष तथा पृथ्ट के अक्ष को धारण करने वाला तल ग्रीनविच से गुजरता है।
(d) समस्त पृथ्वी पर दिक्पात सदैव ऋणात्मक होना चाहिए।
उत्तर :
(a) पृथ्वी पर दिक्पात का मान 11.3° पश्चिम से 11.3° पूर्व के बीच परिवर्तित होता है।

प्रश्न 2.
कमरे के ताप पर किसी स्थायी चुम्बक में –
(a) प्रत्येक अणु का चुम्बकीय-आघूर्ण शून्य होता है
(b) सभी अलग-अलग अणुओं के शून्येतर चुम्बकीय-आघूर्ण होते हैं जो पूर्णत: संरेखित होते हैं।
(c) कुछ डोमेन अंशत: संरेखित होते हैं
(d) सभी डोमेन पूर्णत: संरेखित होते हैं।
उत्तर :
(c) कुछ डोमेन अंशत: संरेखित होते हैं

चुम्बकत्व एवं द्रव्य अतिं लघु उत्तरीय प्रश्नोत्तर

प्रश्न 1.
इलेक्ट्रॉन की भाँति प्रोटॉन में भी चक्रण तथा चुम्बकीय-आघूर्ण होता है, तब पदार्थों के चुम्बकत्व में इसमें प्रभाव की उपेक्षा क्यों की जाती है?
उत्तर :
इलेक्ट्रॉन का चुम्बकीय-आघूर्ण \(\left(\mu_{e}\right)=\frac{e h}{4 \pi m_{e}}\)
इसी प्रकार, प्रोटॉन का चुम्बकीय-आघूर्ण \(\left(\mu_{p}\right)=\frac{e h}{4 \pi m_{p}}\)
परन्तु m_p >> m_e अतः μ_e >> μ_p
अतः पदार्थों के चुम्बकत्व में इलेक्ट्रॉन की तुलना में प्रोटॉन के चुम्बकीय-आघूर्ण की उपेक्षा की जाती है।

प्रश्न 2.
आण्विक दृष्टिकोण से प्रतिचुम्बकत्व, अनुचुम्बकत्व तथा लौहचुम्बकत्व की चुम्बकीय प्रवृत्तियों की ताप निर्भरता की विवेचना कीजिए।
उत्तर :
प्रतिचुम्बकत्व इलेक्ट्रॉनों की कक्षीय गति के कारण उत्पन्न होता है, अतः यह ताप से अधिक प्रभावित नहीं होता है। अनुचुम्बकीय तथा लौहचुम्बकीय पदार्थों के अणुओं में अपना परिणामी । चुम्बकीय-आघूर्ण होता है तथा प्रत्येक अणु स्वयं एक चुम्बकीय द्विध्रुव होता है। इन पदार्थों में चुम्बकत्व इन चुम्बकीय द्विध्रुवों के बाह्य चुम्बकीय क्षेत्र के अनुदिश संरेखण के कारण उत्पन्न होता है। ताप वृद्धि पर संरेखण विक्षोभित होता है जिसके परिणामस्वरूप इन पदार्थों की चुम्बकशीलता ताप वृद्धि पर घट जाती है।

प्रश्न 3.
चित्र में दर्शाए अनुसार तीन सर्वसम छड़ चुम्बकों को समान तल में केन्द्र पर रिवट द्वारा जड़ दिया गया है। इस निकाय को विराम अवस्था में किसी धीरे-धीरे परिवर्तित होने वाले चुम्बकीय क्षेत्र में रखा गया है। यह पाया गया है कि चुम्बकों के निकाय में कोई गति नहीं हुई। एक चुम्बक के उत्तर-दक्षिण ध्रुवों को चित्र में दर्शाया गया है। अन्य दो चुम्बकों के ध्रुव निर्धारित कीजिए।
उत्तर :

चुम्बकों के निकाय में कोई गति नहीं हुई है, अत: परिणामी चुम्बकीय-आघूर्ण m = 0.
इसके लिए एकमात्र सम्भव स्थिति चित्र में दर्शायी गई है।

MP Board Class 12th Physics Solutions

MP Board Class 12th Special English Essay Writing

1. INTRODUCTION
Essay is an attempt which gives expression to one’s thought on a given subject. It is a written composition in well-arranged paragraphs. It deals with one particular subject. Students at school level are not required to write elaborate essays in which great learning and loftiness of language is required. It is enough if they can write English in a clear, simple, and correct style.

2. STYLE
Remember the following rules to acquire a good style:

1. Simplicity. It means expression of thoughts in simple language and simple words. High sounding words and complex sentences have no place in expression.
2. Clarity. Ideas are to be expressed in such a clear language that it can easily convey the meaning to the reader.
3. Originality. The language must consist of original English words and structure of sentences. Foreign words, Latinised style, colloquial phrases, and slang in expressions must be avoided.
4. Accuracy. Words and phrases should be exact. Wrong words and inaccurate expression give wrong or different meanings. Generally, they mislead the readers.
5. Brevity. Brevity means to use the least number of words in expressing the ideas. Conciseness makes the language idiomatic and forceful.
6. Unity. Sentences of a paragraph should have only one main idea. Unnecessary details must be left out. It saves the time of the reader as well as yours.
7. Order. Clauses and sentences should have proper connection with one another. Loose phrases of sentences destroy the beauty of the style and add to its ugliness.

3. HINTS FOR ESSAY-WRITING –
The following hints should be kept in mind while writing an essay.

1. Use short sentences and write short paragraphs. They should vary in length.
2. Be vivid in your description of anything. For this purpose comparisons and contrasts may be used. They do not destroy the beauty of your description.
3. Say everything that is necessary on the subject. Always keep your aim clear before you. Never write vague things. Vagueness corrupts our habit of writing to the point.
4. Be clear and concise in your remarks.
5. Write a neat and legible hand-writing. It is the key to success.

4. HOW TO WRITE AN ESSAY
When you are asked to write an essay on some particular subject, begin as follows:

1. Understand the Subject Fully. Have a clear idea of what you are going to write. Do not set to work before you understand the particular aspect of the subject.
2. Collection of the Material. By putting intelligent questions to yourself upon the subject, collect material for your essay in hand. Note down the ideas as they strike you. After writing them to arrange them in order.
3. Planning. Having collected ideas, begin preparing the outline. Group together the allied ideas and reject the unnecessary ones. Arrange them under a few main headings and draw up a”scheme.
4. Having written the outline, begin writing the essay. Divide your essay in a few paragraphs. Each paragraph should deal with one heading.

5. STRUCTURE OF AN ESSAY
An essay can be divided into three parts:

1. The Introduction.
2. The Body.
3. The Conclusion.

1. The Introduction : The introduction of the essay should be brief. A short quotation or a proverb serves a good purpose. The first sentence should be striking and interesting. It should be a keynote.
2. The Main Body : The beginning should lead naturally to the main body. We should deal with the necessary and relevant facts. The body is the longest and the most important part of the essay. It should be split up into suitable paragraphs of different lengths. The end of one paragraph should prepare the reader for the next paragraph.
3. Conclusion : The end of the essay must be as striking arid interesting as the introduction. The last sentence should strike the attention of the reader. It should leave a lasting impression on his mind. The end should be natural and not abrupt.

6. ERRORS TO BE GUARDED AGAINST
Avoid the following errors while writing an essay:

1. Definitions, except in the case of any elaborate essay.
2. Introductory remarks by way of showing one’s humility and thus exacting the sympathy of the examiner.
3. Quotations, except from very familiar authors.
4. Use of too many metaphors and similes.
5. Repetition of words and ideas.
6. Colloquial phrases or slang expression.
7. Foolish abbreviations.
8. High sounding words.

Now let us see the examples of essays.

1. India of My Dreams
(M.P. Board 2010, 2012)

India was great in ancient time. Students from China, Portugal, Japan, Greece used to come to study here. Cities of Nalanda and Takshshila were famous as educational centres. Every one wants to see their country at the peak of glory. I am not an exception. I have sweet and beautiful dreams of my country. I am a resident of India. It is my beloved motherland’.

I wish that my country may rise to a great nation. It should help its neighbours and may give them the message of peace. I wish that my country should become militarily strong and be fully prepared in this nuclear age for defence. I wish that no foreign country may dare attack again, like the plundering raids of the olden times. Hence, I wish it should become the first-rate world power in terms of military strength.

I wish that there would be no illiterates in India of my dream. I wish that India should introduce such a system of education as should enable every citizen to earn his or her living. I wish that my government should educate each citizen. Adult education, female education and education for children should be made compulsory. I wish that India should become a highly industrialised nation. It should start cottage industries in villages and heavy industries in cities. India will make great progress in the field of science and technology. Education will be free for all. There will be no illiteracy. Every person will enjoy free medical treatment.

I wish that our country should make great progress in science. India should make use of atomic energy for peaceful purposes. It should send rockets to the space and should advance in the field of science and make her own military requirements. We should establish big factories to produce all sorts of machines. India will have a strong army to safeguard its frontiers. It will neither commit any aggression nor tolerate any aggression.

I wish that in India there should be no poor person. As Gandhiji said, “We have to wipe away every tear from every eye.” Freedom becomes meaningful only if we help the poor folks to rise in prosperity.

I would like to see India as a great nation in the world. These are my dreams about its future. There would be no corruption, adulteration, ill use of drugs and social, evils. Every one would like India, his motherland and would be ready to sacrifice every thing for this motherland.

2. Role of Newspapers and Media (M.P. Board 2010)
Or
Value of Print Media in Our Society

It is our natural instinct to know what is happening around us. Nobody wants to live in ignorance. Hence, newspapers have become part and parcel of our life. We cannot live without them. The morning newspaper is as indispensable for a good start to our day as the i morning cup of tea. It is our mental breakfast and unless we go through the ‘headlines’, we feel uneasy. What to talk of the city-dwellers, even the people living in the villages are seen [ eager to go through the newspaper to know what is going on in the world. Therefore, a newspaper is the basic need of the common people.

A newspaper, in the modern society has great social and educative value. It is a common t media of giving news along with views. Its principal aim is to supply news, information with different views through comments, articles, and editorials. It is, therefore, called the ‘people’s university’. Different people expect different things from the newspaper. A businessman i wants to know the market trends, a farmer is eager to know the weather report, a book reader wants to know about the latest arrivals. A newspaper satisfies them all like an intimate friend.

It is evident that a newspaper holds a great power in a democratic country. It maintains a close connection between the government and the people. It deeply influences public opinion. It spreads political awareness among the mass, the most important function done i by the newspaper in a democracy. It ‘exercises’ such tremendous influence that it not only bring about major changes to the lives of ordinary people but can even overthrow a government. The editors of the newspapers have, therefore a heavy responsibility.

A newspaper becomes a power of evil if it distorts truth, and presents only the negative side of a thing. Sometimes, it has been said that the newspaper publishes false reports in hatred and enmity between communities and nations, subjects, and sovereigns. Some of the newspapers take interest in provoking class hatred. They poison the mind of public with communalism. In order to win cheap popularity, baseless gossip is spread. This misleads the public. A good newspaper should not misquote or misrepresent, the facts. It should promote the feeling of national integration instead of encouraging fissiparous tendencies.

Overall, newspapers have become a thing of necessity in modern times. Therefore the government should give as much liberty to them as it may be possible to give. The only restriction that the government should impose on them, should be that they should not be allowed to publish sensational news and dirty advertisement. If this is done, newspapers will surely do valuable service to the country by maintaining its objectivity and fair standard.

3. Afforestation The Need of Today
Or
Trees and Human Life [M.P. Board 2012]
Or
Trees are Good Friend to Humanity (M.P. Board 2013)

In the early periods of civilization, large parts of our country were covered with forests. The increase of the population of our country has led to the shrinking of the forest area. The forests which purify air have been cut down and new cities and industries have been established in their place. The cutting of the forests cause what is called “The Green House Effect”. It results in the heating of the earth’s surface or global warming which has serious consequences on life of this planet. As a result coming generations are likely to suffer from incurable diseases. And what is extreme, even the existence of human kind might be in danger. Afforestation is the only measure that can be taken to avoid these disastrous havocs.

We know that Chipko Movement was started by Shri Sunderlal Bahuguna to stop indiscriminate felling of trees in the Himalayas. However, an all-out effort is needed. We can’t thrust this responsibility only on the government, on the public institutions, or on any particular person. It is the duty of all and all must work together to make it a success. A planned government effort is needed in every state. The government must invest in the afforestation of hilly and desert areas. It must raise green belts in areas which are subject to rapid erosion.

However, at the same time, awareness among the common people is greatly needed. Steps must be taken to create massive people’s movement, with the involvement of women, to achieve the objectives and minimise pressure on existing forests. People, as a whole, must be motivated for plantation and protection of trees as their social duty. Saplings are planted every year, no doubt, but in absence of proper care they die by the next monsoon. Who is to look after them? It is the general public, whose pious duty is to water and save every plant growing on the land in their neighborhood.

Educational institutions can play a key role in this regard. They can instil in the younger generation, the need for planting trees. There are many social organisations which should come forward and encourage common people for plantation. These organisations should also help the government so that it may implement its various programmes on conservation of forests successfully and rapidly. Our existence is bound up with the trees and therefore trees must be planted, especially, on the road side and near railway tracks.

Forests are very important for us. It is unfortunate that we are ignoring its significance and are playing havoc with this one of the most vital part of the nature. Hence, we must be aware of this fact and save trees to save our lives and our existence. We very often talk about environmental pollution but do nothing in this regard. Let’s take a pledge to plant trees in more and more numbers and promote others for this noble cause.

4. Science and Civilization
(M.P. Board 2009, 2016)

Science has been a wonderful phenomena for mankind. It has considerably altered the world by its wonderful discoveries and inventions. Revolutionary changes have been brought about which could not have taken place in the absence of science. It is science that produced and developed human civilization. The process of science and development of human civilisation have run parallel. Science has been a potent factor to shape the history of man’s civilisation on earth. Our forefathers lived a primitive life and we are now living in an atomic age. This long leap from the jungle to the atomic civilisation has been possible only through science.

The concept of civilization is different from that of culture. Civilization includes the physical development while culture signifies the inner growth. All the industrial, agricultural, and technological developments are the essential parts of a developing civilisation. We are now living in a world of dazzling glitter. Machines have reduced much of the human labour and suffering. They are serving humanity like faithful servants. Ours is a push-button civilisation, which depends upon tools, implements and machines.

There are specific features that make a civilization complete. The entire structure of civilization stands on some solid factors. The first condition for a true civilisation is that it must include the fulfilment of the primary human necessities just as food, clothing and housing. It is a matter of proud privilege that the present generation is enjoying better living conditions. We have better clothes to wear, better and nourishing food to eat and a better house to live in than our ancestors. In this respect, we can assume an easy superiority over them. There is no denying in the fact’that it is science which has made our living conditions better. We must be grateful to science for its many advantages.

The other factor which makes a civilization meaningful and useful is leisure. If a civilisation cannot provide leisure to the people, it is not a civilisation of human beings but of brutes. If a person is busy filling his belly, from morning to evening, he does nothing different from what an animal does. The poor fellow struggles for his survival throughout his whole life and this is what the people of hunting and pastoral age did.

Science has bestowed numerous gifts on mankind. Means of transport and communications, medical facilities, electricity, agricultural machinery, recreational facilities etc. are such gifts of science to man. The blessings of science have made human life smooth and easy. Unfortunately, the gifts of science have not been shared by all human beings equally. No civilisation is complete unless the gifts of science are enjoyed by all. The gap between the rich and the poor, has widened. This has hampered the uniform development of our civilisation.

Science has invited lethal weapons which can destroy mankind in the twinkling of an eye. The atomic weapons have multiplied. Science can take away from us in a moment what it has given to us during the last several ages.

The terror of war is always hanging up on our heads like the Sword of Democles. The survival of humanity is facing a horrible peril. The future of our civilization is uncertain if the atomic weapons spark the Third World War. If science has made civilization strong on one hand, it has made it weak on the other. If the gifts of science are not properly used, time is not far when we shall see the end of human civilization.

5. The Burning Problem of India
Or
The problem of Unemployment In India
Or
Any Burning Problem (M.P. Board 2009, 2010, 2012)

Unemployment has emerged as a major national issue. During the last many decades, it has been increasing day by day. It is the burning question of the day. We find long queues before the Employment Exchanges. This problem of unemployment has been baffling our planners ever since we attained freedom. The population of India has already crossed the dangerous mark of 1200 million. Such enormous and abnormal growth of population has belied all calculations and plans.

There are several factors or reasons that are responsible for the large-scale unemployment in the country. First, the population is increasing very rapidly. Employment opportunities have not increased with the rise in population. The rise in population must be controlled in order to end unemployment.

Education has reached the remotest villages of India. Educated persons run to the cities in search of jobs. We find many graduates and matriculates running after white-collared jobs.

They do not like to work in factories, mills, or in the fields. This has given rise to unemployment.

With the advent of automatic machines, employment opportunities in offices have declined. Moreover, educated people do not like to work in the villages. To end this tendency, factories should set up in the villages. The youngmen would, then, stop coming to cities.

India is predominantly an agriculture country. There is no dearth of raw materials in India. We must make India an industrial country if we wish to control the mounting pressure of unemployment.

The government must plan in such a waythat men and women should be greatly benefited. Our system of education is not employment oriented. There is no vocational training in our schools or colleges. Most of the people do not like to work with their own hands. Small scale or rural industries have been badly neglected. Cottage industries can absorb most of our unemployed youth. Had we taken to rural industrialisation, cottage and small-scale industries instead of establishing big multi-crore industrial projects, the problem of unemployment would have been solved to a large extent.

Our government is fully aware of the serious results of the problem of unemployment. New Education Policy lays stress on vocationalisation and de-linking of degrees from jobs. Small-scale industries are being set and educated youths are being given all possible encouragement to set up their own enterprises.

Importance of Games and Sports Essay for 12th class

6. Importance of Games and Sports (M.P. Board 2010, 2011, 2012)
The real education is one which can make a student intellectually sharp, physically strong and morally sound. It develops and strengthens the three aspects of our personality—mind, body and soul. In this sense, games and sports are the basic needs of life. Unless the development of the mind and body goes hand in hand with a corresponding awakening of the soul, the former alone would prove to be a poor, lop-sides affair. Therefore, games and sports must form an integral part of the education of our youth.

So far, physical education has been neglected in our educational system. Games and sports have been woefully neglected in our schools and colleges. Our education has been concerned only with earning degrees and diplomas. No wonder then our young men have started hating physical labour. Our graduates who come out of universities with gold medals are physical wrecks. It darkens their future completely.

Hence there is a need to change our attitude towards games and sports. Some people think that sports and games are unimportant things that people do, at times, when they are not working. They consider them only as amusement like the cinema or radio, such things, they think are harmful for the studies of a student who must at all times, continue to stuff his brain with facts and figures. In fact, sports and games are of great value, especially to students who work with their brains most of the day.

Sports and games make our bodies strong and keep us healthy. Little brain work can be done by an ailing person. A sound mind resides only in a sound body. Physical exercise is essential for health. Every nerve, every sinew and every joint of the body gets strengthened through games. However, a good health is not the only thing we get through them. They give us a valuable practice in making eyes, brain, and muscles work together. In tennis, for instance, our eyes see the ball coming, judges its speed and direction and pass this information on to the brain. The brain has then to decide what to do, and to send its order to the muscles of the arms, legs, and so on, so that the ball is met and hit back where it ought to go. All this must happen with very great speed. Only those who have had a lot of practice at tennis can carry out this complicated chain of events successfully.

Sports and games are also very useful for character training. In their lessons at college, boys and girls may learn about such virtues as unselfishness, discipline, and love of one’s country’but what is learnt in books cannot have the same deep effect on a person’s character as what is learnt by experience. Games inculcate in the players the habits of teamwork, discipline is being guided by a captain, obedience to the rules of the games are interpreted by the referee or umpire and spirit of sportsmanship in taking the defeats along with victories with a smile. If we want a disciplined nation, we must give due encouragement to games and sports in our schools and colleges.

Recreational value of sports and games cannot also be denied. After a tiring day in the class-room, in the laboratory, or at your desk, there is nothing more refreshing than an hour in the field. A hot game of hockey, a fast match of football, and an exciting cricket takes off our fatigue. One feels fresh once again for any amount of work.

Games and sports thus must be compulsory for all students. Colleges and schools should have proper equipments and facilities for the students. The teams may win or lose, games play their wonderful role in making students active and agile in their life.

7. Communal Harmony
(M.P. Board 2009)

Amity between different communities in the country and absence of any friction and tension among them is known as communal harmony. In countries like India, it is very important, being a precondition to internal peace, which is essential for progress and development of the country. As we know, India has got multiplicity of religions and very nature of the culture is composite. However, religion has never been a source of conflict between the communities in Indian society. Mutual tolerance and high regards for other religions is an age-old tradition of the country, still the vested interest has always been active to create disharmony between them. There were, however, not a single instance some years back where obstruction in religious performance had been a cause of communal riots. This phenomenon in the Indian context is politically motivated and has always been engineered by vested interests. It was there at the time of the foreign rule as well as in the post-independence era.

Communal harmony as such is a highly sensitive issue and cannot be soft-pedaled any more in view of our traditional values, composite cultural heritage and secular character of our state but the main problem is how to maintain communal harmony at administrative and social levels. There is lack of political consciousness among the common people due to illiteracy. Secondly, anti-social and professional criminals have been playing a key role in communal riots and flare-ups as agents of vested interests and their hirelings. Finally, there is a need of an effective mechanism to deal with it. Present mechanism is not so smooth. It lacks coordination and people’s involvement. The intelligence agencies report in advance to the District and State authorities about the communal tension and the element actively associated with growing tension and potentials of disturbances etc., but generally no action is taken and authorities wait for the riots. It is only thereafter that police moves .in for action and curfew, is clamped to control the situation. During curfew arrests are made for violations.

For the last seventy years, Ram Janambhoomi-Babri Masjid issue has been a major root of communal disharmony. Muslims and Hindus are face-to-face on this issue. Earlier, the communal riots on this issue have taken many lives in Gujarat. Three bogies of a train in which Ramsevaks were returning from Ayodhya were burnt by a mob of 2,000 Muslim fundamentalists at Godhra railway station. As a result, 58 persons were burnt alive. Suddenly in reaction to it, Hindus started burning the properties and men and women in different areas of Gujarat.

To begin with, therefore, the first thing is to have a fresh look at it and amend our approach accordingly. Foremost in the process, thus, is resolute toil on the part of the government to protect the foundation pillar of the Indian state. We must tackle the situation wisely.

With fresh approach to the problem, fresh measures should also to be taken to deal with it effectively. The measures would include suitable amendments in the existing applicable law, pertaining to apprehension of breach of peace and criminal conspiracy against the state and people of India. Anew mechanism involving individuals and social organisations on different levels to watch over the situation replacing existing local peace committees will have to be evolved to help the administrative machinery in taking preventive and follow-up action in cases of attempts and conspiracy of breach of communal harmony. This will lead our country to the path of glory.

8. Wonders of Science
Or
Science and Human Happiness (M.P. Board 2010)
Or
Science: A Good Servant but a Bad Master (M.P. Board 2011)
Or
Science in Our Daily Life (M.P. Board 2014)

Science is a tremendous concept. It has done wonders for us. It has gifted a number of wonderful objects. There are reasons to consider science to be a blessing. Science has helped men to conquer the forces of nature. It has added new comforts to the life of men. It has made men superior to all other creatures. It has made the rulers powerful because of gun powder. The life during the dark ages was unsafe. In those days looting and murders were common after sun-set.

Faster modes of travelling and improved means of communication have established order and security. Today, we can have lunch in India and supper in London. It has conquered distance. Similarly telephone, telegraph and wireless have helped us to save time and send messages at any moment. The modern devices help us and save our time from kitchen to fields. Now, man has a greater amount of leisure.

Science has brought success in every field of our life. Man has almost conquered diseases. He has checked polio and plague. Surgery can now show miracles. By applying science to industries, men have been able to raise the living standard of common people. Most of the people were naked in ancient period. They were very poor. They had no food to fill their bellies. They died like cats and rats due to starvation, cold, and excess of work. Science has now made large scale production. Almost every one is provided with the common necessities of life.

As a matter of fact, a scientific invention cannot be blamed for the tragedy of man. After all, an atom bomb does not prepare itself or explode on its own account. A discovery of science is lifeless, obviously, it can never control man. Seeing in this light, science can never turn out to be a master, it is always a slave. But is has blinded man who thinks everything is possible, thus ihvents and discover more.

Men should always think of both the positive and negative aspects of discoveries of science. When man loses the moral values in life, then he thinks of destroying innocent people. He also becomes one of its victims. Nobody should be a slave to science and an enemy to human civilization. It should always be used for peaceful purposes. It must be tackled wisely because any kind of mishandling can bring a doom to our life. Its devastating aspect is almost beyond control.,

9. Computerization: Its Advantages and Disadvantages
Or
Computer that Changed Our Life

Science has gifted us so many wonderful things that have affected our style of living and made life easy going. Computer is one of them, it has played an important role in improving the conditions of advanced nations. We can effectively realise our dreams through proper use of computers.

India declared its computer policy in November 1984. It has opened a new beginning of computer revolution in the history of India. The first computer in India was built in 1966 by Tata Institute of Fundamental Research. After a while Bhabha Atomic Research Centre added to computers in a series. Computer is now manufactured on a commercial basis. This has given a further momentum to the computer revolution in India. The establishment of the Electronics Corporation of India was a momentous event.The use of electronics will not accentuate the problem of unemployment. On the other hand, it will provide employment to a lot of people. Electronics can be safely and carefully made use of in agriculture weather-forecasting and soil testing.

The ruling party made use of computer in the last Lok Sabha and Assembly elections. Computer played a great and important role in the analysis of election results.

The Government has established National Information Centre in New Delhi under Electronics Commission, which is fitted with the most advanced and accurate computers.

The use of computer has proved to be very beneficial in banks. Computers, at all the branches of all banks, have been installed. It is being increasingly used in transport system. The international airlines have already got it.

Its use in Post and Telegraph, military and corporate houses has revolutionised the working of these departments. It has been found of immense use in the statistical department for the purpose of data analysis.

Indeed, advantages of computer are many. It makes calculations much faster and more accurate than in all industrial countries of Europe and USA, on a large scale. If data are correctly fed into a computer, then it can check and correctly examine answer books at a much faster rate. That is why computer is in use in all the educational institutions of the developed countries of the world and developing countries like India are making abundant use of it.

However, on the other hand, we can’t deny that computer has made us crippled. We are now completely dependent on it. Sometimes, computer data are corrupt and everything is lost that we store in it. So, we need to be more careful with computer while handling data as hackers can easily mishandle important information.

10. A Visit to a Historical Place (M.P. Board 2014)
Or
A Visit to the Taj Mahal (M.P. Board 2015)

I had a great desire to see the Taj Mahal, the most graceful and matchless tomb at Agra. So, I made use of the kind invitation sent to me by my dear friend in the summer vacation. I had heard much about the beauty of the Taj Mahal and had heard of how Mughal Emperor, Shah Jahan, had at a great cost built the world famous tomb for his beloved wife, Mumtaz Mahal, as a token of his great love for her. It is said that it took twenty years to build it, and that twenty thousand men were employed to complete it.

I, with my friend, reached the Taj in the evening just before sunset. We went into the beautiful garden to enjoy its straight walks, tall dark cypress trees, smooth green lawns, beds of glowing flowers and its flashing fountains. There rose up before us the wonder of the world. I found it all of white marble. I enjoyed the sight of a splendid white dome rising up in the midst with four tall white marble minarets around it, one at each corner of the raised platform on which the great tomb stood.

At a little distance, the Taj Mahal looked small and delicate like a fairy palace but as I got nearer, I saw how large and stately it was. When we went up the marble steps, the dome seemed to soar high up into the blue sky and the clouds which were red and gold with sun-set light. The movement stood on the bank of the river, Yamuna. The water of the river was all gold in the sunset glow and made the building look more beautiful than ever.

We went inside. We saw the marble tomb within. They were decorated with precious stones and the beautiful screens of carved marble. There, we thought of the beloved queen whose body lay below and the great love of the king who had spent his wealth in putting up the lovely memorial to her. The real tomb of the queen laid in a small room which one could reach by descending some steps. The hall was charming for its most beautiful patterns of marble work. The pavement was made with the squares of white and black marble. Everything in this hall, i.e. walls, screens, and tombs, are all covered with inscriptions from the Quran. There are also flower designs inlaid with beautiful and precious stones of different colors.

When it was full moon, I persuaded my friend to take me again to see the Taj. We enjoyed the wonderful moon. It looked like a building of pearl or a palace made of silver. It seemed to be made of white cloud. The shining white marble, the black shadows, the soft moonlight, the silence, and the sweet-scented garden all made it a. sight never to be forgotten.

The Taj has been described differently by the poets. It has been described as a “Poem in Marble” or a “Dream in Marble”. The late world-famous and Nobel Prize winner poet, Rabindranath Tagore wrote many poems on the Taj Mahal which are very excellent. No photographic description or portrait can describe its full beauty.

It is no wonder if visitors come from far and near in thousands to have a look at the Taj Mahal every year. It is, indeed, one of the seven wonders of the world.

11. Corruption in India
Or
Corruption—A Cancer of Society

Corruption is a deep-rooted menace that has eaten into the vitals of our society. There is hardly any sphere of social, economic, political and religious activity that is free from corruption of some kind. Corruption has become so common that most of the people have come to accept it as a part of their life.

Bribery and corruption have increased greatly after 1947. The growth of democracy and industry, the system of licences and permits for setting up enterprises, securing quotas of raw materials, imports and exports and exapansion of trade and commerce are responsible for the increase in corruption. Stringent laws against corruption have proved to be effective in curbing this evil.

Corruption flourishes as long as there are people who are prepared to give bribe and accept it, directly or indirectly. Each one of us has a weakness for easy money. People are prepared to do anything or stoop to any extent of taking graft in order to maintain their so-called standards of living. People who indulge in corruption maintain double standards. On the one hand, they accept bribe and on the other, they urge people to be honest and pure. Such hypocrisy compounds the offence.

It is not difficult to locate the causes of corruption. Corruption generally breeds at the top and then gradually filters down to the lower levels. Gone are the days, when people who joined politics were fired by the spirit of serving the nation. Those who suffered for the sake of getting their country freed from the foreigners, only knew how to make sacrifices. They had never expected any compensation for their sacrifices. Those were the times when only the selfless people joined politics. However, unfortunately, the present day politics has become a business like any other. The modern politicians are no longer motivated by any lofty ideals. In order to win elections, they spend huge sums of money with the hope that after they are elected, they would recover much more than what they had spent. When the people in power indulge in unscrupulous practices, a common man also indulges freely.

Government after government have made promises to root out corruption from our public life but this evil has persisted. Of course, there are honest officials but they are in minority. Let us as a nation, contemplate seriously as to what will happen when our public life is loaded with corruption. A certain amount of introspection by those who are in power can only initiate the process of minimising the evil of corruption in our country. If the public in general is indifferent, corruption wil continue to grow like cancer in our society destroying all the goodness. If corruption persists, our country will become a diseased country and continue to be a developing country.

12. My Favourite Game

Game is a part of my life. Right from my childhood, I have been a good player. I take part in all the outdoor games. Everyone has his or her own choices. Some like hockey, others like football, while many others consider cricket to be their best game. The game which I like the most is football. I have my own reasons for liking this game.

Now, you can ask me why I prefer football to any other game. It can be easily explained. The main object of all the games is to give us some exercise. This is one reason why football is my favourite game. It helps our body to grow. It brings a sense of discipline and a habit of endurance in us. A good football player is sure to succeed in any walk of life. He can make a great soldier to defend his country. He can be a clever statesman to run the government. He can continue to be a good sportsman if he is dedicated to his game. He can be anything because his endurance and sense of discipline has taught him to be himself and be independent of his mind.

However, is there no other game which gives hard exercise? Surely none other except, perhaps, hockey but hockey carries many risks for the life of a player. It also makes the player quarrelsome. He uses stick as his weapon. On the other hand, in football, no such risk is involved. One can go on playing without hitting anyone seriously.

Another reason for my choice is that it is very economical. It does not require elaborate and costly equipments. A ball and a well-levelled ground is all that is required to start the game and then it is easy to pick up its rules. We do not require any special coach for it is learnt so easily by boys that they begin to play it in a very young age, long before they are ready to play hockey or cricket. It would not be an exaggeration to say that football is a game which one learns at a very early stage of one’s life.

Like hockey or cricket, football is played by two teams of eleven boys. A team consists of five forwards, three half backs, two full backs, and one goal keeper. The player kicks the ball with his feet and he may touch it with any other part except, of course his hands. The goal keeper, however, can use his hands as well. As a player may be tempted to push an opponent or go for a head of the ball near the opposite goal, so pushing and off side are regarded as a foul play. The penalty for a foul is a risk by a player of the opposite team. The fewer fouls you make, the more chance you have to win the game easily.

The game of football gives us good exercise. We have to be vigilant and alert. It encourages team spirit. It gives a very good exercise to all the limbs of our body It keeps us fit for all the times. No wonder, then, I have a special preference for my favorite game football.

13. A Cricket Match

Cricket is one of the most popular games’of the present century. Of late, it has become quite popular in our country Wherever you may go, when the cricket match is on, people are glued to their transistors or television sets. It appears as if the entire machinery of the Government has come to a standstill and people are concentrating on to the performance of our national heroes, the cricketers.

Cricket has introduced in India a long time ago. Previously, this game was played only by a few aristocrats. The Rajas and Maharajas only could afford this costly game.

In the last spring holidays, a friendly cricket match was played between the teams of filmstars and cricketers. It was played at the Indira Gandhi Stadium. A large number of spectators were gathered there to watch the match. I am also very fond of this game. I also went to see the match.
The match started at 10 a.m. Messrs Derby and Dick acted as umpires. The Cricketers Plus team won the toss and began to bat. The captain sent in Rohan and Chetan, the two good opening batsmen to face the bowling by Govinda and Rakesh.

They had a good start. Rohan could not face the strong and sharp bowling by Govinda. He was bowled before the score was ten. In the next fifteen minutes, Chetan was also caught in the slips.

The batsman, who followed them, played a steady game. Soon one of them opened his ; account with a boundary. He punished loose balls. He squarecut the off-balls beautifully to the boundary. He did not take liberty with the straight balls but he delighted the spectators by hitting hard the loose ones. The bowlers tried their best to dismiss the players. They kept good 1 length and line of the ball. The batsmen remained at the crease till they had scored 60 runs.

Rohan had caught one of them at the corner. The second wicket also fell quickly. After this our bowlers had an easy time. Our opponents could not stand against our hard hitting balls. There was a regular going in and coming out of the players. There were no less than five ducks. The rot did not stop till the whole team was out for a paltry 100 runs.

The second innings started with a new zeal after the interval. Our opening pair hit up 29 when one of them was caught in the slips. Rohan filled up vacancy and scored five boundaries. He was raising the score steadily when his companion went forward to hit a slow ball. He lost his balance and he was stumped by the wicket keeper.

Our next player was a good hitter. He had sent the ball over the boundary thrice and scored a dozen runs quickly. The score went up to 70. Runs came in boundaries and occasional singles were also cleverly stolen between the players. Zafar and Ajay hit out powerfully between , them and the score increased rapidly. It was a fine performance indeed. They were well set when one of the deliveries bumped dangerously high and Zafar, in trying to hit, gave an easy catch to the wicket keeper. Ajay was also caught in the slips. The rest were easily dispersed off and when the game came to an end, Film Plus team won by ten runs and three wickets. It was a hard fought victory for the our players. We returned home clapping our hands and jumping merrily.

14. Democracy in India

India is said to be the largest democracy in the world in terms of numbers. Democracy is the form of government in which people’s will is supreme. At the present day, in big countries, it is not possible for the entire population to gather at one place, deliberate, and control the whole affairs. Government is, therefore, carried on by the elected representatives of the people. Of all the political forms of governments, democracy is considered to be the best. Democracy is therefore, the most cultured and civilised political institution.

Democracy is the temple in which there is only one idol to be worshipped and that is the idol of the people. Democracy provides to its people freedom of thought, speech and action. Elections are held after a certain period. General Elections have been held in India for several times. It shows that the foundations of democracy here are stable. In comparison to most of the neighbouring countries, like Pakistan and Bangladesh, sudden overthrow of governments have been witnessed. Army rules have been imposed on these countries, which curtail people’s freedom.

It is not mere holding of elections that is important but people in India have developed i mature judgement. When they find that a particular political party failed to represent their feelings, people of India have voted that party out. In 1977, the Congress (I) was defeated at the polls. Within two and half years, when the Indian people felt that the Janata Government was unable to deliver the good, they brought back Congress again. In the recent past also, many surprising political changes have been witnessed in the State elections. In Haryana and Punjab, the Congress was defeated at the elections. This is despite the fact that the majority of the electorate is still not very highly educated. However, by and large, people in India have developed mature judgement which is imperative for the success of democracy. The Indian electorate has once again voted the Congress out of power in the recent General elections. Very recently a new trend of governance has emerged, in the sense that no political party could gain majority which resulted in the formation of coalition government continuously for two consecutive terms, first by the NDA and second by the UPA.

It is a matter of serious concern that many drawbacks have crept into our democratic structure. Majority of the political leaders in our country has become corrupt and self-seeking. At times, one finds that democracy in our country is no longer the government of the people, for the people, and by the people. It is only a handful of self-seeking leaders who are ruling the country without any regard to the public welfare, which should be the important aspect of any democracy. Once elected, the ruling party forgets the voters and starts filling up their own coffers. This is certainly not healthy for the continuance of democracy. When we compare Indian democracy with that in England, we wonder at our public morality. The politicians, here, feel reluctant to leave their seats of power once voted by the people. For the success of democracy in our country, what we require is clean public life of the politicians. The recent scandals about the 2G scam have given a shock to the democratic set-up in India. If the people of our country are vigilant, only then there lies some hope for the future of democracy in India.

15. Television and Education
Or
Educational Value of Television

Television is a wonder to our life gifted by science. It has become a craze in the present day world. It has both advantages as well as disadvantages. The educational importance of television cannot be underestimated. In all the developed and developing countries 6f the world, television is increasingly being made an important aid to education. Its audio-visual quality makes educational programmes more effective and interesting. Schools are making full use of its potential for imparting education. In our country, television is. not confined only to the cities but it has gained popularity among the villages. In all the schools in Delhi, television is being freely used as a useful means of education.

Everyone would acknowledge that television is the most effective means of imparting scientific education. The best teachers can teach the largest number of students in the most effective way at a particular given time. In subjects like Science and Geography, there are many things which can be shown on television rather than taking the students to the actual places. For example, the student can have the actual glimpse of snow-fall on the mountains through television. This demonstration of the real things is sure to have a lasting impression on the minds of the students, rather than merely telling them about those things. Scientific experiments can be shown to the students with the help of the television.

Students can be shown the celebration of important national events like the celebration of Independence Day and Republic Day. The students can listen to the important speeches of the national leaders on television. The actual scene along with the particular gestures of the leader will be remembered more vividly by the students.

Physical education is becoming an important aspect of modern education. Certain games can be taught with the help of television. Expert physical instructors can demonstrate the various body movements in various physical exercises. The popular T.V. programme presented by famous cricketer, Sunil Gavaskar has become very popular among the budding cricket players. The 24 x 7 channels makes it a point to show the direct telecast of all important national and international sports events. Test Matches on T.V. virtually hold the entire nation’s work for the duration of the match. Television can be very useful in imparting technical education to the students. Hence, one can’t deny the fact that television serves a major role in the field of education effectively.

16. If I Were the Prime Minister of India

Dreams often are unreal. Becoming the Prime Minister of a country like India may sound strange, yet if, given a choice, I would like to be one, if fortune favours me and if the public of oUr country elect me. As the Prime Minister, I would like to achieve the ideals of real democracy by bringing out many new reforms in the present set-up.

The first thing, I would like to introduce is moral education in our schools and colleges. At present, there is lack of morality. People are selfish and corrupt. Moral education to the youngsters would make them selfless and inculcate in them the idea of service to people. The youngmen and women are the future leaders and statesmen of our country. If the young people are selfless, they can inspire others by their personal example.

My second ambition after becoming the Prime Minister is to remove the curse of poverty from our society. I will have to introduce reforms in agriculture, so that more and more young men get attracted towards it. I shall provide suitable incentives and loans to the young people to start their own enterprises. I shall ensure that employment is given at least to one member in i a family, so that none starve.

Most of our countrymen are superstitious and ignorant. This is due to lack of education , and enlightenment. I shall make education absolutely free. It shall be controlled by the State. shall devise ways and means to screen the boys and girls at regular stages and provide them the.right type of education-according to their aptitude. Higher education will be restricted only to those who excel in their studies. I shall change the entire education system so that most of the young men do not run after white-collar jobs.

My efforts as Prime Minister would be directed to knit our country as a united and strong nation. I shall not give any importance to religion. In fact, I would see to it that religion remains only a personal affair of an individual. The State would not give any importance to religion as such. I will see to it that people do not fight in the name of religion and that no political party exploits the religious sentiments of the people for their advantage.

I shall set such an example of selfless and dedicated service to the people that my successive Prime Minister may emulate my example. Such is my vision if I ever get an opportunity to become the Prime Minister of India.

17. Any Burning Problem (M.P. Board 2009,10, 11,12, 15)
Or
Growing Population: India’s Menace
Or
The Problem of India’s Increasing Population :
Or
Any Current Burning Problem of India (M.P. Board 2013, 14)

Indian life has turned to be critical. There are so many problems that have made us panicky. I Increase in population is one of them. Famines, floods, earthquakes, and riots often occur. The government is doing its best to solve these problems but the problem of increasing population is the most dangerous. The population explosion has taken a rapid stride in India. According to the Census of 1971, the population of India was 54.8 crores. It became 68.4 crores in 1981 and 84.4 crores in 1991. It has crossed 100 million according to the 2011 census report. This presents a horrible situation. The explosion of population has complicated the problems of poverty, illness, unemployment, and many others.

The population in India is growing rapidly. The advancement and expansion of medical science has resulted in lower death rate. Along with it, the illiterates of our country give no thought to the national problems created by this rapid growth of population. The children are thought to be the gifts of God.

The population explosion in India has brought about many severe consequences. The health of the mother runs, down and that results in the rearing or weakening, which make a weak, dull, illiterate, and poor nation. Therefore, for the welfare of the family and the nation as a whole, it is very necessary to check the growth of population. Every citizen of India should try to limit his family. For this ‘Family Planning’ or ‘Family Welfare’ is needed.

Growth of population may be prevented by observing celibacy and self-control. However, in the present day atmosphere, it is rather impossible. So, the negative check has been chalked out by the government. Loops, Nirodh and contraceptive tablets have been invented. The government is making a vigorous propaganda for it. People are being encouraged to go under vasectomy or tubectomy operations. Family Welfare Centres have been set up in all parts of the country where ‘Nirodh’ and contraceptives are sold on nominal charges or distributed freely. Operations are also managed there.

We should realise that the children are products of choice, not of chance, or God’s gift. ‘We two and ours two’ slogan should be maintained by every citizen. We should be watchful for the future progress and prosperity of the nation and observe ‘Family Welfare’ programmes. People should be educated to be wise enough to control this situation. There is a need for public awareness which alone can solve this problem, otherwise a time will come when there will be no place even to stand on the Indian land and no food to eat for anyone in India.

18. Value of Discipline

Discipline is a way which follows the order. No nation can be great unless its people are disciplined. Discipline in life leads to success. No country, school, college, or home without discipline can function properly. Thus, it is necessary in all walks of life. Discipline starts from home. To respect the authority is the base of discipline. Children must obey their parents and elders. Parents should guide them properly.

Discipline is very necessary for the continuance of a well-regulated and orderly life. It is needed in every phase of life. Its importance in our country today is very great. The freedom of the nation can be safe only when we learn the lesson of discipline. Discipline is required for the progress and betterment of individual in his life. It is the guide and the guardian of a man’s life. All the great men have risen to the heights of success and glory by being disciplined in their lives. Loose discipline in family, in the classroom, in the army, and the field will lead to the path of ruin.

An indisciplined army is unmanageable. It will suffer defeat in the battle field whereas a disciplined army fights unitedly and comes out victorious. The discipline of Indian army is well known all over the world.

In a classroom, no teacher can teach his or her students. It is for the class to maintain discipline. One learns discipline first at home and then at school. To obey set rules is discipline.

In a family, the head can’t run it smoothly if the members don’t maintain it. In an assembly, all the members must observe discipline if they want to do any good job successfully in time.

Discipline should be the way of life without which we. would face, complete chaos. We will make no progress at all. It would provide an order and perfection to our life. If there is no discipline in any field of life, there will be no progress. Even in family, if we lack discipline, it is sure to be doomed. Hence, we need to discipline our life.

Infact, discipline is very essential in all walks of life. In its absence there will be utter disorder, confusion, and chaos. No nation can progress in its absence. It is the key to success. Hence, it must be followed by all.

19. Politics of Coalition
Or
Indian Politics Today

At present, Indian politics is under the process of development. Although right from the time of the freedom movement, the process is on but during the last twenty years, there have been a lot of changes. Due to the selfish motto of political parties, the aim of getting power to rule things has gone the worst.

Indian politics has lost the real component of fair practice. The means should be right and pure to achieve the object but in our country, now the attraction of power is so much that no body cares for the mean. For example, for winning the election they, adopt all those malpractices which are immoral in our society. After election, horse-trading goes on to capture power. Ministers, officials and leaders of political parties adopt immoral ways and means to earn money.

After 1985 many cases of corruption were detected in public life in which leaders, – government servants, contractors, brokers, and anti-social elements were involved. The fashion and tradition of commission increased the corruption in all walks of life. During‘the last ten years, there were a lot of scandals in which so many ministers, secretaries, directors, government officers and servants are found involved. The cases .of share scandal, hawala, urea and chara are the worst which have opened the new chapter of corruption in public life. Though these scandals are mere examples, there are a lot of such scandals which are still to been brought into light. Indeed there is a lot of corruption in our public life. Bribery has become a courtesy. No work is done without it. Almost all the measures adopted to control it have failed head long because most of our leaders, political workers, government officers, public servants, contractors, brokers, businessmen, traders, industrialists are directly or indirectly involved in the cases of corruption. Some of them have been caught while the others are still beyond reach.

At present, even the representatives of people such as some of the MLAs; MB*s, ministers, government officers and servants are following the path of corruption and they are making hay while the sun shines. The whole system has become so spoiled and corrupt that it needs well planned serious efforts.

As, now-a-days, no party is getting absolute majority at the centre, so the politics of coalition is going on. It is giving us a weak government. Moreover, the country has to fall into mid-term polls due to coalition politics. This new trend now seems to be the way of Indian politics. In coalition form of government, no single party gets a majority. Many of the parties form the government. It becomes very critical for one to run the government and control the parties of different ideas. For example, two successive governments had ruled India—one, the UPA and now the NDA. This trend is not at all good to the nation.

20. The Role of Opposition Parties in a Democracy

In a parliamentary system of government, the party or the group of parties commanding majority forms the government and remains in power as long as it enjoys the confidence of popularly elected House. Regarding seating arrangement, the House is divided into two wings. On the right hand side of the Speaker, the ruling party or the parties are allotted seats and in parliamentary terminology these are called as treasury benches while on the left hand side of the Speaker,*the opposition party members or parties are allotted seats. Parties and group on either side have their own elected leaders. The Prime Minister is also the leader of the House ., while the leader of the largest opposition party enjoys the status of the leader of Opposition in _ the House. There is a prescribed procedure for this and they are accorded recognition of their status by the Speaker as per the rules and regulations and established norms in respect, thereof.

The government is free to determine the policies and programmes and make decision, so long as it retains power that is again subject to the approval of the House in a prescribed manner.

The Opposition parties play very significant role in a democracy as representatives of the people who have returned them to the House to safeguard their interests. With this view, they criticise the government in case, the latter ignores them or conceals facts and they resort to protestation in the House and at the public level. It counts very much for the awareness among the people over the specific issues of national importance and raises levels of political consciousness among them.

Most impressive and dominant role of the Opposition in a democracy is that of a ‘watch dog’ of the system. In such countries, where there is a two-party system in vogue, the opposition party forms a ‘shadow cabinet’ to exercise vigil over the performance of the government. This is more true in case of United Kingdom. Two-party system is also in vogue in United States of America. Since there is no parliamentary system of government, the Opposition party in the House of Representatives of the US Congress (the lower House of the Parliament) forms as many committees as the ruling party does and presents their views over the policies and performance of the US administration in national and international affairs before the official – committees. Joint committees are also formed on important subjects or issues.

In countries where there is multi-party system in vogue including India, the Opposition . parties try to cooperate among themselves over particular issues. Arbitrary and despotic behaviour of the government is checked by the Opposition parties demanding information and debate in the House. It is the opposition in the Parliament that has a very important role of check and balance to play in the larger public interest and correct democratic practices.

Members of the Opposition parties are also included in the advisory committees attached to the respective ministries. All the measures of the government connected with the respective ministries are discussed and finalised by them. Opposition plays a significant role in it through its recommendations.

Therefore, in shaping of the legislative measures, Opposition has a say or at least influences , it. Still, if their recommendations are ignored/they have another chance, when the bill is I introduced in the House and debated.

Opposition in the Parliament enjoys a good status and the members of the House have a privilege of raising such issues that are more relevant to the cause of public; more particularly when the government overlooks them or conceals the facts related to them. It is very clear, therefore, that the role of opposition parties is more vital to the healthy growth of democracy and in the larger public interest.

In extreme eases of confrontation, if the government is all powerful to crush the Opposition, the latter is potent enough to make a stir against the former and force them to exit by means of mass movement and agitation. Only then they can save the democracy. Plato has rightly said, “The punishment of wise men who refuse to take part in the affairs of the government, is to live under the government of unwise men.

Though the real role of the Opposition parties is to appreciate the government in its progressive works and to oppose and control its negative role but now the concept seems to have changed completely. To oppose the government has become their only prominent role. It mars the progress of the nation.

21. Pollution: A Threat to Our Life (M.P. Board 2016)
Or
Pollution: Need for Environmental Consciousness
Or
Environmental Pollution (M.P. Board 2011)

The unsustainable lifestyles and consumption patterns of the industrialized countries have led to the worst environmental degradation. As far back as in 1992, Earth Summit at Rio de Janeiro 1 highlighted the facts adding that poverty is the main setback in controlling and reforming of the environmental pollution for the poor and developing countries. It called for a global partnership for environmental protection. Agenda 21 adopted at Rio de Janeiro addressed the pressing problems of the day with over 2500 recommendations for action in social and economic areas, such as combating poverty, changing patterns of production and consumption, conserving and managing natural resources, protecting the atmosphere, oceans and biodiversity, preventing deforestation, and protecting sustainable agriculture.

The major problems of the environment are recognised as global climatic change, ozone depletion, water and air pollutions, deforestation, arid resource degradation. 23 billion tons of carbon dioxide is released in the air by burning fossil fuels causing Greenhouse effect. The greenhouse gases are mainly contributed by the industrialized nations. By the middle of the 21st century, earth’s temperature at present level of heat emission would go up by one to three degree Celsius and the sea level would rise between 30 to 100 centimetres.

India has witnessed alarming environmental degradation in the last two decades. It is the sixth largest and the second fastest producer of greenhouse gases. The key environmental pollutions related to industries in India are water pollution, soil erosion, groundwater : contamination, and deforestation. Indian rivers are also suffering from high level of pollution due to enormous municipal wastes, industrial effluents, and agricultural run-offs. According to expert findings, 70 per cent of India’s surface water is severely polluted. As per the government statement in 1992, three fourths of the total waste water generation is due to the municipal waste which is half of the total pollution load.

Consequent to it, fresh water resources are depleting very fast and water-borne diseases , are on an increase, which account for 2/3rd of the total illness in India. Air pollution in India is the highest by vehicular sources to the extent, of 64 per cent, 16 percent by thermal power, 13 percent and 7 per cent by industry and by climatic sector . respectively. The average level of suspended particulate matter in Kolkata, Mumbai, Chennai and Delhi is very high and these are included in the list of ten metropolitans of the world in respect, thereof. These cities have reached critical level while Kanpur, Nagpur, and Ahmedabad are hitting the same. Chennai is found to be moderate.

With respect to land pollution, it is the disposal of solid and toxic municipal and industrial wastes. The average per capita solid waste generation in India is to the order of 360 to 400 grams per day. This waste leads to affliction of respiratory diseases.

In case of pollution control for environmental reform it is very important to note that a partnership of highly industrialized nations with the poverty stricken and developing countries is a must for sustainable development. It implies the help of the former to the latter, which includes transfer of the latest non-pollution technology. This has been the main stress in the Rio-Declaration. In June 1997, Earth plus five summit was held in New York to review the programme adopted in ‘Agenda 21′. the conference concluded that the targets were’ not achieved—annual emission of carbon dioxide, blamed for global warming, continued to rise, freshwater scarcity remained, and depletion of forest cover was not being checked. Another conference was held in a Japanese resort, Kyoto, in December 1997, to check global warming. Participants agreed to meet binding target between 2008 and 2012.

The steps to control pollution in India included environmental clearance for major industrial activities based to impact assessment before site selection. Introduction of unleaded petrol, low-sulphur diesel, and higher emission norms throughout the country in a phased manner is the second significant step. Besides this, efforts are to be intensified further to control ” pollution in 22 industries in various towns and cities that are critically polluted. The industries are to comply with such emission and effluent standards as may be notified in a time-bound manner.

22. Pollution and Human Life

Man is an important part of the biosphere. He has an intricate relationship with forests and trees. The biosphere and ecosystem are self-sustaining. Nature maintains a balance in land, ‘ water, air and all the living organisms in the world. Any imbalance in the biosphere is called environmental pollution. The grand industrial development, green revolution, transport expansion, rapid growth of cities and accidental management of natural resources have badly affected environmental balance. The pollution of air and water will soon reach a point when no place on the earth will remain safe. Due to large scale industrial and human settlements on grand scale, many rivers have become gloomy and dark. The large scale industrial water and oil poured in the sea have started killing marine life.

Undoubtedly, the modem technological development has been the main cause of polluting our air, oceans, and rivers, etc. It is a matter of great importance that our rivers are becoming dark. Fishes are rotting on the sea shores. Trees are withering and cities are filled with foul air. Toxic chemicals are finding their way into our food. When the normal composition of air is changed, air becomes polluted.

The main causes of air pollutions are combustion, manufacturing processes, agricultural ‘ activities, use of solvent, and nuclear energy programmes. Combustion can be described in three types. Fuel burning, transportation, and refuse 1 burning. All these three kinds of combustion release several types of gases. These gases pollute 1 air. They also cause pollution. Chemical plants, combustion plants and plants for waste recovery come under this category. The polluted things released from these processes make the air unfit for human consumption. Agricultural activities are another source of air pollution. The use of chemical fertilizers and manures and burning of field waste pollute the atmospherical air.

Several types of solvents are used in spray-painting, polishing of furniture/dyeing, printing, and dry cleaning. The solvents produce hydrocarbons which pollute air. Various measures can be adopted to control pollution. To trap smoke particles, chambers should be made. Lofty smoke stakes should be built. Gases should be discharged through exhaust pipes higher in the air. Chemical industries should not be allowed to be set up on the banks of rivers. Waste materials should be subjected to anti-pollution treatment.

In view of the great-danger to mankind, many countries in the world have passed laws to prevent pollution. However, it has been seen that anti-pollution laws are not being obeyed. Terrorism is the most talked-about news item in today’s life. Every morning, we come across sensational news and reports of the acts of terrorism committed by terrorists in the world. Sometimes, it is a murder of an eminent politician, sometimes it is the kidnapping of an envoy by terrorists in order to blackmail a government to concede to their just or unjust demands. Hijacking of aeroplanes is a common phenomenon nowadays. Bomb explosion, taking place in crowded areas, is yet another criminal act of the terrorists.

There are many other forms of anti-social or anti-national, inhumane activities. Fish plates are removed from the railway tracks, and the wells or water tanks are poisoned by the terrorists.

These anti-social or anti-national activities are performed by the terrorists in order to call the attention of the National Government or the world community to a certain problem and to get their just or unjust demands fulfilled.

Terrorism is an international problem which has clouded our lives and made them insecure. We do not know at what moment we may be the victims of a bomb explosion, or a railway accident or the hijacking of an aeroplane. No one has forgotten the Bombay bomb-blasts, the Godhra incident, Akshardham attack, WTC attack, and the Russian Massacre.

We may classify terrorism into two categories: positive and negative. Positive terrorism is one in which the aims are good. For example, a number of Indian patriots took to terrorism against the British government to force it to grant freedom to India. The terrorism of South Africa and North Ireland, etc. may be included in this category. This type of terrorism is understandable since its aims are good for mankind but we would not recommend such means for even right ends. In order to secure the achievement of noble ends, right means must be employed, as Mahatma Gandhi did.

Negative terrorism is one in which an unsatisfied section of a community holds the entire community to ransom in order to get its unacceptable demands fulfilled.

Terrorism has neither boundaries nor any caste, creed or culture. It can occur anytime, anywhere in the world, sometimes without any intension. Terrorists have no humane heart. They spare none not even the innocent little children. No doubt terrorists are the people who have been created by our society. It is the misguided zeal of a few genius who are spreading it into the world. We must handle .them with care, otherwise the whole world will be doomed. There is a need to spread a public consciousness.

The whole world should fight against it unitedly.

24. Dowry System—A Social Evil

Since the da\vn of civilization, dowry system has been prevalent in our society in one or the other form. It is one of the biggest evils of our society. It is an insult to the sacred institution of marriage, Parents pay huge sums of money, so that their daughter may live a happy married life. The groom’s parents try to get the maximum from the bride’s parents. Unreasonable demands have been made by the groom’s parents and sometimes, the marriage ceremony is abruptly stopped in the absence of sufficient dowry. Fabulous amount.of cash, refrigerators, cars, coloured television sets, scooters and even houses are demanded in dowry. The parents of the girls have to incur heavy debts in order to meet the demands of the greedy in-laws of their daughters. No wonder, then the, birth of a daughter is not liked by any Indian parents.

Giving dowry is a very old custom. Even in the past, the parents of the girl have been giving dowry in the form of gifts. Its supporters give a number of arguments to justify it. According to them, it is, a fine method of setting up an establishment for their newly-weds. Some say that a daughter-in-law who brings adequate dowry with her commands better respect from her in-laws. Op the other hand, a bride without sufficient dowry feels insecure and uneasy.

All these are absurd arguments and cannot, in any way, justify this social evil. There is no point setting up one establishment by upsetting the establishment of the bride’s parents. Modern girls are educated and in many cases, are not dependent upon their husbands for their upkeep. In such cases, it is foolish to insist on dowry as the regular earnings are no less than dowry. A girl can gain confidence only from her merits and not from the dowry.

It is the duty of all enlightened citizens of our country to fight out this evil. We must get rid of our society of this curse. Anti-dowry Act has been enforced but if the people do not co-operate, the evil of dowry cannot be eliminated. As a matter of fact, all dowry seekers and givers should be boycotted socially. Educated boys and girls should bow not to marry the sons or daughters of those who demand dowry.

This social evil is eating up the foundation of our society. In a country like India, it is foolish of us to promote and become a part of dowry which brings us down and make us still a developing country.

25. Politics of Religion :

‘Politics’ and ‘Religion’ are two separate concepts which have no connection. One is purely a worldly affair while the other is beyond this world. One is the human creation while the other relates to the supernatural. Let us understand in a more clear way. The term ‘religion’ applies to the belief and the way how and to whom one worships. Its origin dates back to the origin of mankind. It means to say that it grew along with the growth of human being. Primarily, there have been four major, religions—Hindu, Islam, Christianity, and Sikhism. All these religions take human beings to their salvation. The followers of these different religions follow different Gods and different ways of their worship. With the growth of humanity, a number of other sub-religions have been born but one thing is very clear that followers of all the religions believe in a superpower and try to get its blessing. It means that religion is the super concept that relates the physics to the metaphysical but there has been a very dangerous turn in the idea of religion. Politics has changed the meaning of religion and religion is being used for politics.

According to our Constitution, India is a secular country which provides all its citizens the freedom of faith and worship in their own way but in the present scenario, this religious freedom is being misused. Religious appeals are made by the leaders for securing more and more votes. Religious feelings of the people are aroused for political gains. The demolition of the disputed structure in Ayodhya is one of the examples of the misuse of religion. As a result ? there were communal riots all over the country. It was as if people had lost their mental balance and were out to destroy their religious rivals. It was forgotten at that time that India is a land of many religions and all religions are given equal respect and weightage. However, the issue was handed over to the Supreme Court and the Government was bound to follow its judgement.

Ag our life has completely been politicalised, religion has taken a prominent place in every field of our fife. Politics is the way through which we occupy the government, rule the country and establish contacts with the mass. On the other hand, religion is the most sensitive way through which we take ourselves to a completely different world which is transcendental. While politics is completely a physical phenomenon related to this world, religion is completely related to a metaphysical phenomenon which has in no way any relation to this world. It means both stand apart. However, in the present context of our way of life both have been intermingled I which has created a chaotic situation and we are completely confused.

This chaotic situation is the outcome of selfish attitude of the politicians. Today, politicians are not concerned with the welfare of the nation. Instead they think only for the next election. Hence they try to create their vote banks in either way. For this they apply every possibility and make all efforts to win over the majority of the people in their favour. They use money, caste- factor, regionalism, lingualism, etc. for this purpose. They have not spared the pious religion. Time to time religious issues are raised to blackmail the sentiments of the people following a particular religion. -There are a number of examples which our country has witnessed in recent years. Advani’s Somnath Yatra, Godhra Carnage, Mumbai blast, 1984 riots, operation blue-star, demolition of Babri Masjid are some of the well-known incidents which have haunted our minds and we are compelled to think over the misuse of religion for vested interest of a few misguided leaders or political parties. Very recently, we have witnessed the hue and cry over the arrest of Jayendra Saraswati, the Shankaracharya of Kanchikamkoti Pith. He has been the prime suspect of a murder of one of his assistants. Some of the leaders have raised their voice of protest against it. How much are these protesters justified in protecting an accused of murder? Should such persons not be treated like other criminals? It is a time for retrospection to think over the misuse of religion for such purposes. Religion should not be the way to get votes. It should be kept apart from politics. It should not be corrupted with politics.

26. Growing Fashion among the Youths
Or
Evils of Fashion

Fashion is the term which applies to the trend and style that youths adopt according to the changing world. It sets our dress, behaviour, food, likes and dislikes, etc. in order to match with the changed scenario. In old days, people mostly followed the traditional pattern of living set by our predecessors on the basis of their religious values and beliefs. So, the names like Dasharatha, Rama, Krishna, Radha were the most common in the society but now Tom, Dick, and Harry are in fashion. Now, the fashion is set according to the Bollywood and Hollywood. Actors and Actresses of the films have become the role models. Now it is very difficult to distinguish whether’Puppy’is your pet baby dog or your own son or daughter.

Fashion is not a word that is unknown to anyone today. The whole world has become crazy for fashion and tries to go ahead in this race. The Western countries in general are the homes of fashion. France is known for the latest fashion throughout the whole Europe and now our India too is in the grip of fashion where people, in general, and youth, in particular, have become so mad after it that they hardly think about decency. They must have their clothes cut according to the latest rogue, their hair made up according to the latest style. They never bother about the expenditure on their fashion.

The youths copy the actors and actresses. Some of them see a film to copy the latest fashion. They make a liberal use of cosmetics and beauty-aids. They do it in a competitive spirit to look smart, up-to-date and attract their friends. The girls are perhaps the worst sinners in this regard. They don’t hesitate to put on tight clothes, as light as possible, even though the dress is entirely inconvenient. They just wish to look like their favourite actresses. Even parents too are not less faulty. They buy the dress according to their daughter’s choice. As a result the girls have become fashion conscious, so much so that they have no time to think that the dress they have put on is decent or not. Similar is the case with young men. Wearing tight pants with latest hair-style and holding a cigarette in between the fingers feeling themselves as very smart.

These fashion-loving young men and women never realise that they are wasting their precious time and energy which are to be used for study to make life brighter. They carry their pocket combs to their classroom and comb their hair even in the course of a lecture. They put burden on their parents and spoil their hard-earned money. By and by, they become the prey of bad habits. They start drinking as a mode of fashion and sometimes they even take drugs too.

The cinema and T.V. are the most important sources of fashion. They circulate the latest style of dress and hair among the youths. These fashions exercise strong fascination over them. Most o£the cinemas and serials are exclusively based on fashion. The female characters expose their body in minimum clothes while the male characters try to overpower the young minds sometimes with their hair styles, sometimes with their art of speaking, walking, attacking their enemies, etc. All these are baseless.

Fashion no doubt is the up-to-date mode of living but one must be conscious of one’s culture and background. Everything is not acceptable everywhere. The fashion which we follow in our society- is not meant for us. So, it appears to be odd and instead of taking the young generation the right path it leads them to some kind of perversion and moral degradation. The previous generation doesn’t promote this western culture, as they think it corrupts our society’s values. Exposing dresses of girls are questioned as the men of our society did not take it as a trend. We must stop such practices by way of moral education and proper care to our young generation.

27. Energy Crisis

The growth of human being has travelled a long journey. It was the greatest achievement of primitive man when he discovered fire with the help of a stone. With this, human history moved very fast. Later on, a number of discoveries and inventions were made which changed human life completely. Energy is such a great invention which made our life more and more comfortable. It has become the -most needed necessity for us. It has created a crisis also.

In the industrially advanced world of today, the demand for energy is increasing day by day. We have machines and factories, we have buses, cars, trains and planes, and ships and submarines. Energy is needed to run them but this is not all. Man hankers for a cosy and comfortable life. Hence, he has become a little but lazy. He does not like even to wind his watch. So, energy is being used for running clocks and watches, typewriters, shaving razors, and many more things. It seems as if everything will be paralysed if there is no energy. Wood, later on, coal was the first source of energy. Then came oil and passing through the stage of atomic energy, man is now looking forward to solar energy.

We are naturally anxious to think about our future because we know the bitter truth that < a*day will ultimately come when we will have no more coal or oil. It will mean energy crisis, for which we ourselves are responsible. People who have made careful calculation feel that at present level of exploitation, the coal deposit will last till 2080 and it is also true that the poor quality coal with the carbon content of 40 per cent only, is not conducive to generate electricity.

It is also very difficult to harness the uneven distribution of coal. Hence, man is on look out for other sources of energy. Our present hope seems to rest on nuclear power.

Nuclear energy can be obtained both through fusion and fission processes. Enormous amounts of energy is released from small quantity of fuel in both these processes but we must be aware of the fact that nuclear power is full of risks. The use of nuclear energy gives rise to pollutants and hence pollutes our environment. In fact, the pollution caused by the use of nuclear energy from fission process is much more damaging than the pollution caused by burning fossil fuels. The dangerous nuclear radiations can damage and cause irreparable damage to cells and, in some cases, even lead to death.

The world will thus face with serious energy crisis. The condition of India is no better. With growing population, the demand for energy is increasing day-by-day. Since India has limited coal and oil reserve and power generation from coal and oil is also very costly, the government is taking steps to supply energy for non-commercial purposes from various sources such as bio-gas.

Scientists all over the world are trying to meet the challenge. They are trying to harness solar, water, and air reserves. Hydro-electric’power is cheaper, so are air mills. Solar energy too has bright hopes for man. However, it is very expensive to establish the necessary infrastructure for tapping solar energy. Giant discs are made to concentrate the sunlight on the thermal generators which use this sunlight to produce energy.

Thus all possible efforts will have to be made to save us from total darkness.

28. Distance Education

Distance education is a new trend of education which generally takes place when a teacher and student (s) are not face-to-face but are separated by physical distance and various electronic media are used to bridge the instructional gap. Before ten years, this system or trend was not thought as a means of education because ‘to take degree’ was not the sole aim of a student. Instead, people thought that regular classes provide real knowledge to the students and therefore, there should not exist any alternative to it but with the progress of science, electronic media, new electronic equipment, the situation has been changed. Through TV’s, educational programmes, the correspondence education can be made to be understood in a better way.

Research comparing distance education to traditional face-to-face instruction indicates that teaching and studying at a distance can be as effective as traditional instruction when the method and technologies used are appropriate to the instructional tasks, there is student to student interaction, and when there is timely teacher to student feedback. As regards with experiments in the laboratory, students can have better understanding than in school labs. Now distance education is covering the whole field of education from academic to technical fields.

Population is increasing rapidly and in this age of science, education is considered a must for all to maintain the standard and status of a happy man. Trends in education are, therefore, changing fast to make it (education) reach to everybody. As a result distance education system is getting popularity day by day and now it has been a popular mode of learning not Only for the formal courses but for professional courses too. MBA, MCA, CA, ICWA, BCA, and many other professional courses are available through distance learning these days. The modern students have accepted this new mode without hesitation due to its various advantages. The contribution of TV programmes regarding distance education is praiseworthy.

Distance education is full of possibilities. Its growing popularity itself explains the truth. Nowadays many prestigious universities and institutions are serving the society through this system. It is a boon for those students who really want to pursue their education but have no time to attend regular classes. Distance education provides them opportunity for this. It is an effective option to continue education.

However, one trend is alarming in the system. Almost all the institutes conducting this system are merely interested in inducting students and providing degrees. That’s why some say that this is merely a system to obtain degrees, anyhow but education does not mean degrees only, it is much more than that. At present this despondent method has taken a unique place.

The electronic media, new electronic equipments, conferencing facility, etc. have provided ample scope for distance education to emerge as a strong alternative, especially, in India. The key to effective distance education is focusing on the needs of the learners, the requirements of the content, and the constraints faced by the teacher, before selecting a delivery system.

However, its success depends on the integrated efforts of students, faculty, facilitators, support staff^and administrators.

29, Role of the Citizens in a Democracy

India is a country with-the largest democracy in the world. Democracy means a government by the people, of the people and for the people. They do this by electing their representatives of the government. All those citizens of the country who have attained their adulthood have the right to vote in. a democracy. This is perhaps one of the most important rights because it determines the kind of government that comes to power. Obviously, the role of the citizens is of great importance in a democracy. They have to be conscious of both rights and duties. They have to know what they should expect from their elected representatives. The citizens should be aware of the problems of their region as well as of the whole country. Only then they can understand whether the government is taking the right steps for their welfare or not. It is possible only when we give importance to our education and acquire knowledge about current events and policy making through newspapers, magazines, televisions, public meetings, etc.

As democracy allows its citizens to express their opinion in public, therefore, the citizens have full right to freely criticize the government, if they feel that it is not discharging its duties properly. However, their way of opposing the government must be decent. They should not take violent steps for this purpose. The government on the other hand should give due respect to the views of the people speaking out against it.

Sometimes, it has been seen that people neglect voting in the elections. They feel that their vote will not make any difference to the outcome. If they do not involve themselves in the electoral process, dishonest and self-seeking candidates are likely to get elected. Hence, the citizens must exercise their right to vote in a proper way. As good citizens, they must take interest in the welfare of their country. They must always remain ready to help for good causes. Democracy can be strengthened if its citizens have a clear view of their own rights and the rights of others. A democratic State particularly depends on the quality of its citizens. If citizens do not take interest in politics, a democratic State might also become undemocratic day by day. Hence, all the citizens must be loyal to their country in the best possible way.

Good citizens always respect the laws of their country. They keep an eye on the enemies who break these laws. They are, therefore, always ready to put down crime and help the guardians of law in arresting criminals. Not only this, they respect other religions too. They keep in their mind that India is a secular country and that they have to maintain its essence.

In a nutshell, the citizens must be honest, trustworthy, dutiful, and vigilant. A democratic nation can flourish only then.

30. India’s Nuclear Policy

India has always believed in peace and she has always promoted it by all mean. She was never in favour of manufacturing a nuclear bomb which only brings ruin and disaster to millions of people. However, as many countries, whether developed or developing, have conducted many nuclear tests, it became a necessity for our country to go nuclear. Further, the rising trend of intervention by the industrialised nations in the internal affairs of developing nations among which India is also one, was one of the main reasons which compelled India to divert her nuclear resources towards nuclear weapons. There was an urgent need to protect our national security because national development depends on it. Development is inseparable from national security. Finally, India conducted three nuclear tests on May 11, 1998 and two more tests on May 13,1998 in Pokhran.

However, India’s stand on the role of nuclear weapons is quite dear. She is not in race ; with any other nuclear power. She has exercised her nuclear option without violating any international obligations in order to deter the threats that would have compromised her national ’ security. India is very much clear on this point that she will employ nuclear energy for peaceful purposes only and what is more important is that India affirms her commitment to no-first-use of nuclear weapons and not using these weapons against those countries which are non-nuclear weapon States. Nuclear weapons will only be used in retaliation against a nuclear attack on Indian territory or on Indian forces elsewhere. Thus, India’s main objective to have nuclear weapons is to provide a solid base to the national security system. She is sure that she will never misuse her nuclear capability.

Thus, India’s nuclear policy is very much responsible. It aims at providing minimum credible deterrent. The most significant aspect of the policy is that it is intimately tied up with continued commitment to total nuclear disarmament, which is*the need of the hour. Nuclear Weapons are deadly and nuclear war would result in total destruction as the whole planet would be totally devastated and survivors would face terrible conditions. Hence, it is necessary to speak out against the nuclear armament. Nuclear energy must be used for peaceful purposes and India wishes arms race should be stopped by all meAnswer:

I However, it is unfortunate that the five major nuclear powers are reluctant to give up their monopoly over production and deployment of nuclear weapons while denying a similar ’ privilege to other countries. Under these circumstances, it is really an admirable step for India to have nuclear weapons so that others may not befool us or they may not take an aggressive turn against us.

Thus, India’s nuclear policy is highly appreciating and others should follow it in order to maintain peace in the world but we have Pakistan in our neighbourhood which has no belief in the principle of no-first use of nuclear weapons. Pakistan maintains the first strike option in its nuclear policy and has refused to sign an agreement on no-first-use. Whatever may be the attitude of other countries, India is firm in her decision and is not going to misuse her nuclear capability.

31. Science and Peace

Science has made wonders in recent times. It has revolutionised the life in every field such as travel, transport, communication, recreation, agriculture, industry, medicine, trade, and commerce. We have electricity which has made our life comfortable in various ways. We have atom bomb, a great source of power. Now, it is up to us whether we use science for good purposes or take undue advantage of it. No doubt science has placed in the hands of man extremely destructive weapons which may ruin the whole world in seconds but it neither compels man nor creates a situation to make use of them. It is our greed and madness for power that urge us to use destructive weapons because we want to finish each other.

Undoubtedly science has contributed a lot towards world peace to which we must be obliged. Science has given quick means of transport and communication which help us in winning wars more quickly. Hence no long war is possible. Railways, steam ships and aeroplanes make it easy to send troops and food supplies to distant places in a very short time. Thus, the enemy is promptly checked.

The means of communication such as telegraph, telephone and wireless play a significant role in checking war or war-like situation. The speedy means of communication help the administrators in bringing the critical and violent situation under control. Once Eisenhower, the than President of America, had told that atom and hydrogen bombs have secured world peace in a more viable way. The people of the world could not apprehend the meaning and were greatly surprised to read this comment but the President was very much right. It is a fact that nuclear weapons are destructive. If war breaks out and these deadly weapons are used, then it is certain that the whole civilisation will come to a complete destruction. This horror of modern science compels the nations to think several times before going to war.

The means of recreation can be used for establishing peace in the world. The horrible scenes of war, the miserable conditions of people after war, and the scenes of destruction can be depicted on the screen so that the people can take some lessons from them. The after effects of war can be broadcasted from the radio. All these things can make man to determine not to wage war.

Scientific inventions have given us valuable machines. With their help, production has been increased manifold and now even the backward and poor countries have begun to enjoy a better standard of living. War is no doubt a curse and it must be avoided at any cost. It is possible when the good of each individual is brought out to the fore. We do not suffer with split atom but from split mind. It is in the mind of man where war is first fought, then on field. When the sense of brotherhood passes away from mind and when we forget kindness, goodness and fellowship, we enter into wars. So, we are responsible for wars, not science. However, man today has become more conscious of the necessity of world peace than ever before. He has begun to use his scientific knowledge for peaceful purposes.

32. Status of Women in Society

There are two main pillars of human life-man and woman. Both share equal responsibility in the making of society and hence, both are supplement to each other but from the very beginning, there has been a big question mark on the status of women in our society. Everyone talk about their role and responsibility but none care for their position. They have been exploited and ill- treated right from the beginning of the creation.

No doubt in the days of the epic age, women enjoyed great respect among people. Even in the great modern books, their position remained respectable. In Manusmriti, it has been said, “God resides where women are respected” while in modern age Napoleon Bonaparte told, “The hands that rock the cradle rule the world.” However, the reality is something else. Women have been put behind walls from ages. ‘Sati Pratha’ is the bitter truth which shows to what extent our women folk has been exploited. Child marriage and a contemptuous attitude towards the widows are another examples of women exploitation. Raja Ram Mohan Roy was the first who raised voice against these unhealthy systems prevalent in Indian society. He took up the cause of the women and worked hard to abolish ‘Sati Pratha.’ It was due to his courageous work that Indian women dared to come out of Purdah. They got education which provided them opportunities to develop themselves at all levels and in due course, they surpassed the men. Today, we see women in every field. They are marching shoulder to shoulder in every walk of life.

Apart from teaching school children, women are now pilots, receptionists, police officers, doctors, engineers, etc. The elevation in the status of the women sometimes creates confusion among us if Sita and Draupadi had been born in the same country. The previous condition was due to the lack of education but now the spread of education among jvomen has completely changed the scenario. They are occupying key positions almost every field of society. Our country is progressing undoubtedly in this way but sometimes, it appears that over-exposure of women is a suicidal attack for our future. On the one hand, we are not still ready to forget the image of Sita and Savitri and on the other, we are tempted to watch the over exposed movies on TV screen with the little kids of our family. Our modern progressive girls are imitating the fashion very fast which is still not acceptable in our society. As a result it creates lots of problems in society. We must allow women to stand by themselves but they should also be taught our culture arid civilization.

This imitation creates problems since the society is still standing on those controlling customs which has only suppressed women. Women are controlled but the men who cast their lustful eyes on are spared saying the clothes were too appealing for men to handle.

33. The Place of English in Modern India

After India got Independence, a controversy was at its peak whether English should continue or not. There were two views which gave their own arguments for and against the existence of English in India after freedom. Some people opposed English because they thought that it Was a foreign language, the language of the British and therefore, with the end of their rule, their language should also be abolished but it was not easy to abolish it at once. Hence it was given a lease of fifteen years and after that it was to be replaced by Hindi as the national and official language of the country. However, when the time for the replacement of English by Hindi came, there were lots of opposition from all sides, especially from the South. Nothing could be done in such an atmosphere and finally it was decided that English would remain the official language along with Hindi.

English, thus got a permanent position in India. It was also felt that in a country where there are many languages, cultures and religions, English would be used as a link language. It was necessary for the existence of unity of our country. In the present scenario, English has . become the most influential language. Anybody who has good knowledge of English can easily establish himself or herself in the society.

In the field of education, science, technology, engineering, law, medicine, commerce, , industry and the diplomatic services, English continues to enjoy commanding position. Without English we can’t imagine to enter in these fields. Most of the books are available in English. , Hence, its knowledge enables us to read more and’more books on different subjects.

English is also an international link language. This is the only language which is used to 1 establish communication all over the world. It is the library language too. Most of the books of technical subjects, science, history, etc. have been originally written in English. It is used as code and instruction in the management of library. Hence, to gain more and more efficiency in * any field of life only English language can be helpful.

English has become the only widely accepted means of communication in the world. It makes interaction easy. Interaction among the people, living in different parts of the world, ‘ promotes enrichment of culture. We learn differentway^of living and we update our knowledge only through interaction. Thus English has occupied the most significant place in India. Once Nehru said that we should keep our windows open to see the world. English is that window which shows us the world. English has become our necessity. We can neither do nor improve without it. It is the second widely spoken language. Hence, we cannot ignore it if we wish to achieve great success in life. It must be there for its practical advantages.

34. The Educational Value of Travelling
Or
The Advantages of Tourism

The knowledge we get from books is mere theoretical knowledge. It is not sufficient to be ‘ successful in life. To get complete success we require practical knowledge too and it is travelling which takes us from the field of bookish knowledge to the field of practical knowledge. It is not only concerned with pleasure, holidays, travel, and going or arriving somewhere but it makes us know about the habits, manners/and ways of living of other people. We get an opportunity ‘ to learn about others by coming in contact with these things.

Travelling takes us from the world of imagination to the wTorld of reality. It gives us a chance to adjust in the changed circumstances. Books even if they are very good, cannot give us this chance. We come across many difficulties but we successfully overcome them. We never mind minor problems.

A man who has never gone or who avoids to go an excursion develops a narrow outlook. His nature becomes complicated and he feels that his own lifestyle is the best. He fails to understand the effect of environment on the life of man. Through travelling, he can broaden his outlook. When he comes in contact with different people of different cultures, he knows about them and tries to understand them. For a well-travelled man the world is not vast but small. He feels that he is very close to others and the whole world is like a large family.

Thus, from the point of view of national integration, travelling is essential. It establishes x mutual understanding among people of different parts and therefore causes of friction are – softened. It is not necessary that everything should be of our choice. Sometimes, we get things of our choice but most of the times we don’t. Sometimes, we do not find a suitable place for our lodging. At other times, we get food which is not to our taste. On occasions,.language comes in between and creates problems in establishing contacts. When we face such difficulties, we begin to develop our resourcefulness, initiative and tact. And then, we see that there is a solution for every problem. We become more confident and feel spirited.

We say that seeing is believing. In books, we only read about various subjects such as Science, History, Geography, etc. We read that there is the Taj Mahal in Agra and there is the Niagara Falls in the U.S.A. More reading does not affect us to such intensity but when we see them with our eyes, they make an everlasting impression on our minds.

It is, therefore, in May 1992 an ambitious National Action Plan was drawn by the government of India for the growth and development of the Indian Tourism. As a result, the tourism industry has become the third biggest export industry and our country earns large sums of foreign exchange through it.

35. Global Wanning

Global warming means the rise in the mean global temperature to a level which affects the life- forms on the earth’s surface. The factors responsible for this may be both natural and manmade. Warming of the earth due to natural factors is not an unusual phenomenon. The earth’s climate is variable. For example, about 18,000 years ago, the earth was about 5°C cooler than it is today and that was the last glacial period on the earth. Thereafter, the global temperature began to rise.

The earth is kept warm due to what is known as the Greenhouse Effect. Without it the earth would be a frozen wasteland. The short wavelengths or ultraviolet radiation coming from the fun penetrates the atmosphere and is absorbed by the earth. This absorbed energy is also radiated back to space at infrared wavelengths. The earth’s atmosphere contains gases which trap some of the outgoing radiations and thereby, warm the earth. These gases are known as greenhouse gases. Water vapour, carbon dioxide, methane, ozone, nitrous oxide, CFCs and halogens are prominent examples that maintain the global energy balances, both the atmosphere and the surface will warm until the outgoing energy equals the incoming energy.

The increase in the quality of the greenhouse gases in the atmosphere can reinforce the greenhouse effect (increase in temperature of the earth) and lead to global warming. Carbon dioxide is the largest contributor to global warming, as it holds the largest share among the greenhouse gases in the atmosphere. The reason behind it is the natural disorder as well as man-made activities. Volcanic eruptions and forest fire are some of the natural reasons which cannot be checked but the current global trend i.e., deforestation, along with increased combustion of fossil fuels have a cumulative effect on the net increase in carbon dioxide content. We know forests are the areas where the green leaves efficiently utilize carbon dioxide to make their own food. Deforestation reduces this utilization of carbon dioxide. Consumption of fossil fuels and household fuels gives off considerable amount of carbon dioxide. Hence, reduction in the use of fossil fuels is very necessary. Equally necessary is afforestation. It should be encouraged and we, the people, should realize its importance.

Along with reduction in the use of fossil fuels, the use of the household fuels like wood coal, kerosene should also be reduced by encouraging LPG stove and bio-gas plants. They cause less atmospheric pollution. If these methods are not applied, we will have to face serious consequences such as floods, droughts, storms and extremely warm summer. Not only this, the sea levels may increase due to the rise in global temperature.

We cannot control natural happenings but we can control ourselves. We can reduce the threat of global warming to a great extent by applying the ways which have been mentioned above. We have to think as a whole to get rid of this problem. ‘ . ,

36. Internet: The New Revolution
Or
Uses of Internet

The word ‘Internet’ flashes many images upon the canvas of the human mind. The dominant one may be hundreds or thousands of computers and computer networks connected with each other exchanging information. This is the hardware aspect of internet. Its application aspect is the multitude of different services internet offers, by E-mail and others. Yet another image is that of everyone doing their own thing. Through internet, any type of information can be ‘i exchanged like text, audio-video signals on data, etc. Every country has an information network through which it is connected to internet.

Internet is mostly used for Electronic mail, i.e., E-mail messages can be sent to anyone connected to internet. This also helps in development of software data base, which is the base of internet. With the development of multimedia, the interest of people in internet has increased. Through the use of internet and joining of computer, telephone and electronic techniques and development of optical fibre, it is now easy to store and exchange text, Sounds, and pictures.

So, internet is a network of computers joined by optical fibres, through which it is possible to send messages, sounds, text and pictures with the speed of light. Internet arrived in India on 15th August 1995. For three years from 1995-1998, the government had the monopoly of providing internet services but in 1998, it allowed private companies to provide this service to people. Internet is most beneficiary for businessmen, doctors, teachers, students and scientists.

Internet is very useful for common people. By sitting at home, a person can send letters and cards to the members of the family and to friends. They can chat with the like-minded N people on any particular topic. Students can get information on various subjects on internet for their studies. They can even browse through books on internet. Visiting different websites on . internet is known as surfing. Nowadays, one can do anything and everything on internet. One can do even marketing by sitting at home. There are thousands of cyber-shops and e-commerce portals on internet which sell from flowers to even foods on net. A person can watch movies, television, listen to songs and radio, etc.

Thus, internet is gradually becoming a part of our daily lifestyle. In cybercafes, one can .) pay money and surf the net. Nowadays, internet service providers are also providing internet services through cable lines, which are faster to access. However, it is the businessmen who are using internet the most and making it more popular. The fast and economically reliable way of x accessing internet has given a new direction to international business. All the business j transactions and purchases that are going on the internet is known as e-commerce. The biggest * advantage of doing business on it is that the businessmen do not have to sit for the whole time on the shop. With PM Modi, one more step is taken ahead to make Digital India. It has become a major contributor to GDP growth of India. Recent demonetization helped in making the online transaction more in demand.

The Internet has revolutionized every field. Its surprising growth seems to continue in the years to come because it provides great benefit and convenience to the users.

37. Information Technology

What does the term ‘Information Technology’ really mean? Information technology is that technology by which information is processed, communicated, exhibited and retrieved in a fast, error-free and proper-way. Information technology is a technology in Which both telecommunication and computer technologies work together to provide information. Today the world is of information and telecommunication. Everyday new technologies and inventions are being made in the area of information, processing and travelling. There is * hardly any area which has not been affected by this. Due to all this, the word distance sounds ironical in a present-day context. The whole world has become a small place today. Any information can be exchanged by people in a few seconds and that too in proper and effective way without any loss of data while it is being processed. On one hand, all these different ways of telecommunication and information exchange have highlighted the necessity for multipurpose development and growth of information technology, and on the other, the easy access and use of it has boosted the network of information exchange. All this has been possible through information technology like telephone, fax, telex, computers, internet, e-mail, photocopier, printer, scanner, cellular phones, pagers, videophone, digital camera, multimedia, etc.

These technologies are becoming a part and parcel, of our lives and are transforming lifestyles and habits of people all over the world.

The use of computers has increased by leaps and bounds worldwide. Internet and multimedia have now become playthings for children. The internet has revolutionized every field of the world. The government has allowed private companies to provide internet services to people in order to boost up information technology. The internet has put an unprecedented amount of buying and selling power in the hands of all those within a keystroke distance of a computer. Never in the history of commerce have solitary buyers and sellers been able to engage so effortlessly in commerce on all points whether one is a scrap dealer or a collector with an obsession for antiques, the internet is a solution.

Digital technology is playing a vital role in our day-to-day life. In supermarkets and helps for faster processing of films. In the field of agriculture, a digital moisture meter records the moisture in-the soil and tells when harvesting should start. For people who are suffering from hearing loss, digital technology is of great help. It processes sounds that reduce noise, improves clarity of speech, and controls unwanted loudness.

The government of India is very keen to achieve a great deal in the field of information technology. The Indian Institute of Information Technology is being set up at various places in the country. Now we can hope that India will become an information technology superpower in the near future.

MP Board Class 12th English Solutions

MP Board Class 12th General Hindi व्याकरण समास-विग्रह

जब परस्पर संबंध रखने वाले शब्दों को मिलाकर उनके बीच आई विभक्ति आदि का लोप करके उनसे एक पद बना दिया जाता है, तो इस प्रक्रिया को समास कहते हैं। जिन शब्दों के मूल से समास बना है उनमें से पहले शब्द को पूर्व पद और दूसरे शब्द को उत्तर पद कहते हैं। जैसे–पालन–पोषण में ‘पालन’ पूर्व पद है और ‘पोषण’ उत्तर पद है। और ‘पालन–पोषण’ समस्त पद है।

समास में कभी पहला पद प्रधान होता है, कभी दूसरा पद और कभी कोई अन्य पद प्रधान होता है जिसका नाम प्रस्तुत सामासिक शब्द में नहीं होता और प्रस्तुत सामासिक शब्द तीसरे पद का विशेषण अथवा पर्याय होता है।

कुछ समासों में विशेषण विशेष्य के आधार पर और कुछ में संख्यावाचक शब्दों के आधार पर और कहीं अव्यय की प्रधानता के आधार पर तो कुछ समासों में विभक्ति चिह्नों की विलुप्तता के आधार पर तो कुछ समासों में विभक्ति चिहों की विलुप्तता के आधार पर इस बात का निर्णय किया जाता है कि इसमें कौन–सा समास है।

विग्रह–समस्त पद को पुनः तोड़ने अर्थात् उसके खंडों को पृथक् करके पुनः विभक्ति आदि सहित दर्शाने की प्रक्रिया का नाम विग्रह है।

जैसे–
गंगाजल शब्द का विग्रह होगा गंगा का जल।
इस तरह तत्पुरुष समास के छः भेद होते हैं।

1. अव्ययीभाव समास
इन शब्दों को पढ़िए–

इन सामाजिक शब्दों में प्रथम पद अव्यय और प्रधान या उत्तर पद संज्ञा, विशेषण या क्रिया है।

जिन सामासिक शब्दों में प्रथम पद प्रधान और अव्यय होता है, उत्तर पद संज्ञा, विशेषण या क्रिया–विशेषण होता है वहाँ अव्ययीभाव समास होता है।

2. तत्पुरुष समास
इन शब्दों को पढ़िए–
“शरणागत, तुलसीकृत, सत्याग्रह, ऋणमुक्त, सेनापति, पर्वतारोहण।

उपर्युक्त सामासिक शब्दों में ‘को’, ‘द्वाय’, के लिए, से, का, के, की, ‘पर’ संयोजक शब्द बीच में छिपे हुए हैं जो कारक की विभक्तियाँ हैं। दोनों शब्दों के बीच में कर्ता तथा संबोधन कारकों की विभक्तियों को छोड़कर अन्य कारकों की विभक्तियों का लोप होता है।

जिन सामासिक शब्दों के बीच में कर्म है. लेकर अधिकरण कारक की विभल्लियों का लोप होता है तथा उत्तर पद प्रधान होता है, वे तत्पुरुष समास कहलाते है

(i) कर्म तत्पुरुष समास–
उदाहरण–यशप्राप्त, आशातीत, जेबकतरा, परिलोकगमन।

जिस समस्त पद में कर्म कारक की विभक्ति (को) का लोप होता है उसे कर्म तत्पुरुष कहते हैं।

(ii) करण तत्पुरुष–इन उदाहरणों को देखिए
शब्द – विग्रह
शोकातुर – शोक से आतुर।
मुँहमाँगा – मुँह से माँगा।

जिस समस्त पद में करण कारक (से) की विभक्ति का लोप होता है उसे करण तत्पुरुष कहते हैं।
(ii) सम्प्रदान तत्पुरुष
उदाहरण–
शब्द – विग्रह
विद्यालय – विद्या के लिए घर।
गौशाला – गौ के लिए शाला।
डाक व्यय – डाक के लिए व्यय।

जिसं समस्त पद में सम्प्रदान कारक (के लिए) की विभक्ति का लोप होता है, उसे सम्प्रदान तत्पुरुष कहते हैं।

(iv) अपादान तत्पुरुष
उदाहरण–
शब्द – विग्रह
शक्तिविहीन – शक्ति से विहीन।
पथभ्रष्ट – पथ से भ्रष्ट।
जन्मांध – जन्म से अंधा।
धर्मविमुख – धर्म से विमुख।

जिस सामासिक शब्द में अपादान कारक (से) की विभक्ति का लोप होता है, उसे अपादान तत्पुरुष समास कहते हैं।
नोट–तृतीया विभक्ति करण कारक और पंचमी विभक्ति अपादान कारक की विभक्तियों के चिह्न ‘से’ में एकरूपता होते हुए भी अर्थ में भिन्नता है। करण कारक का ‘से’ का प्रयोग संबंध जोड़ने के अर्थ में प्रयुक्त होता है और अपादान का ‘से’ संबंध–विच्छेद के अर्थ में प्रयुक्त होता है।

(v) संबंध तत्पुरुष समास–
उदाहरण–
शब्द – विग्रह
रामकहानी – राम की कहानी।
प्रेमसागर – प्रेम का सागर।
राजपुत्र – राजा का पुत्र।
पवनपुत्र – पवन का पुत्र।
पराधीन – पर के अधीन।

अर्थात्
जिस सामासिक शब्द में संबंध कारक की विभक्तियों (का, के, की) का लोप . होता है उसे संबंध तत्पुरुष समास कहते हैं।

(vi) अधिकरण तत्पुरुष
उदाहरण–
शब्द – विग्रह
शरणागत – शरण में आया।
घुड़सवार – घोड़े पर सवार।
लोकप्रिय – लोक में प्रिय।

अर्थात्
जिस सामासिक शब्द में अधिकरण (में, पे, पर) कारक की विभक्तियों का लोप होता है उसे अधिकरण तत्पुरुष समास कहते हैं।

3. कर्मधारय समास
महात्मा, शुभागमन, कृष्णसर्प, नीलगाय ।
महात्मा – महान है जो आत्मा।
शुभागमन – जिसका आगमन शुभ है।
कृष्णसर्प – सर्प जो काला है।
नीलगाय – गाय जो नीली है।

उपयुक्त सामासिक शब्दों में पहला पद विशेषण है दूसरा पद विशेष्य अर्थात् दूसरे पद की विशेषता पहला पद बता रहा है।

इन शब्दों को पढ़िए–

शब्द – विग्रह
कनकलता – कनक के समान लता।
कमलनयन – कमल के समान नयन।
घनश्याम – घन के समान श्याम।
चंद्रमुख – चंद्र के समान मुख।
मृगलोचन – मृग के समान नेत्र।

इन शब्दों में पहले पद की तुलना दूसरे पद से की है। अर्थात् पहला पद उपमान और दूसरा पद उपमेय है।

जब सामासिक शब्द में विशेषण विशेष्य का भाव हो या उपमेय उपमान का भाव हो तब कर्मधारय समास होता है।

इस आधार पर कर्मधारय समास भी दो प्रकार के होते हैं
1. विशेषण विशेष्य कर्मधारय–जैसे– नीलकंठ, महाजन, श्वेताम्बर, अधपका।
2. उपमेयोपमान कर्मधारय–जैसे–करकमल, प्राणप्रिय, पाणिपल्लव, हंसगाभिनी।

4. दिगु समास –
इन शब्दों को पढ़िए
पंचतंत्र, शताब्दी, सप्ताह, त्रिभुवन, त्रिलोक, नवरत्न, दशानन, नवनिधि, चतुर्भुज, . दुराहा। इनका विग्रह इस प्रकार होगा– .

शब्द – विग्रह
पंचतंत्र – पाँच तंत्रों का समूह या समाहार।
शताब्दी – सो वर्षों का समाहार या समूह।
सप्ताह – सात दिनों का समूह।
त्रिभुवन – तीन भवनों का समूह।
त्रिलोक – तीन लोकों का समूह।
नवरत्न – नौ रत्नों का समूह।
दशानन – दस मुखों का समूह।
नवनिधि – नौ निधियों का समूह।

इस प्रकार के शब्दों में पहले पद में संख्यावाचक शब्द का प्रयोग हुआ है।
जिस समास में प्रथम पद संख्यावाचक विशेषण हो और समस्त पद के द्वारा समुदाय का बोध हो, उसे द्विगु समास कहते हैं।

5. द्वन्द्व समास–इन शब्दों को पढ़िए–
सीता–राम – सीता और राम।
धर्मा–धर्म – धर्म या अधर्म।

दोनों पद प्रधान होते हैं। सामासिक शब्द में मध्य में स्थित योजक शब्द और अथवा, वा का लोप हो जाता है उसे द्वन्द्व समास कहते हैं।’
इन समासों को पढ़िए माता–पिता, गंगा–यमुना, भाई–बहिन, नर–नारी, रात–दिन, हानि–लाभ
समास विग्रह

शब्द – विग्रह
माता–पिता – माता और पिता।
गंगा–यमुना – गंगा और यमुना।
भाई–बहिन – भाई और बहिन।
रात–दिन – रात और दिन।

उपर्युक्त शब्दों में दोनों पद प्रधान हैं, सामासिक शब्द के बीच में योजक शब्द ‘और’ लुप्त हो गया है। कुछ शब्द इस प्रकार हैं
शब्द – विग्रह
भला–बुरा – भला या बुरा।
छोटा–बड़ा – छोटा या बड़ा।
थोड़ा–बहुत – थोड़ा या बहुत।
लेन–देन – लेन या देन।

इन शब्दों में ‘या’ अथवा ‘व’ योजक शब्दों का लोप रहता है। उपर्युक्त शब्द परस्पर विरोधीभाव के बोधक होते हैं।
इन शब्दों को पढ़िए–

दाल–रोटी – दाल और रोटी।
कहा–सुनी – कहना और सुनना।
रुपया–पैसा – रुपया और पैसा।
खाना–पीना – खाना और पीना।

इन शब्दों में प्रयुक्त पदों के अर्थ के अतिरिक्त उसी प्रकार का अर्थ साथ वाले पद से सूचित होता है। उपर्युक्त उदाहरणों में हमने तीन तरह की स्थितियाँ देखीं।

पहले उदाहरणों में दोनों पद प्रधान हैं, ‘और’ योजक शब्द का लोप हुआ है। इसे इतरेतर द्वन्द्व कहते हैं।
दूसरे उदाहरणों में दोनों पद प्रधान होते हुए परस्पर विरोधी भाव के बोधक हैं, ‘और’ योजक शब्द से जुड़े हैं। इसे वैकल्पिक द्वन्द्व कहते हैं। .
तीसरे उदाहरणों में प्रयुक्त पदों के अर्थ के अतिरिक्त उसी प्रकार का अर्थ द्वितीय पद से सूचित होता है। इसे समाहार द्वन्द्व कहते हैं।

6. बहुब्रीहि समास

इन शब्दों को पढ़िए
1. गिरिधर – गिरि को धारण करने वाला अर्थात् ‘कृष्ण’।
2. चतुर्भुज – चार भुजाएँ हैं जिसकी अर्थात् ‘विष्णु’ ।
3. गजानन – गज के समान आनन (मुख) है जिसका अर्थात् ‘गणेश’।
4. नीलकंठ – नीला है कंठ, जिसका अर्थात् ‘शिव’ ।
5. पीताम्बर – पीले वस्त्रों वाला ‘कृष्ण’ । उपर्युक्त सामासिक शब्दों में दोनों पद प्रधान नहीं हैं। दोनों पद तीसरे अर्थ की ओर संकेत करते हैं।

जैसे–
अर्थात् – कृष्ण।
अर्थात् – विष्णु।

जिन सामासिक शब्दों में दोनों पद किसी तीसरे पद की ओर संकेत करते हैं उन्हें बहुब्रीहि समास कहते हैं।

बहुब्रीहि और कर्मधारय समास में अन्तर–
कर्मधारय समास में दूसरा पद प्रधान होता है और पहला पद विशेष्य के विशेषण का कार्य करता है।

उदाहरण के लिए–
नीलकंठ का विशेषण है नीला–कर्मधारय। नीलकंठ–नीला है कंठ जिसका अर्थात ‘शिव–बहुब्रीहि समास बहुब्रीहि समास में दोनों पद मिलकर तीसरे पद की विशेषता बताते हैं।

बहुब्रीहि और द्विगु में अंतर–जहाँ पहला पद दूसरे पद की विशेषता संख्या में बताता है। वहाँ द्विगु समास होता है। जहाँ संख्यावाची पहला पद और दूसरा पद मिलकर तीसरे पद की विशेषता बताते हैं वहाँ बहुब्रीहि समास होता है।

जैसे–
चतुर्भुज – चार भुजाओं का समूह – द्विगु समास।
चतुर्भुज – चार भुजाएँ हैं जिसकी अर्थात् ‘विष्णु’– बहुब्रीहि समास

समास को पहचानने के कुछ संकेत–

1. अव्ययी भाव समास – प्रथम पद प्रधान और अव्यय होता है।
2. तत्पुरुष समास – दोनों पदों के बीच में कारक की विभक्तियों का लोप होता है और उत्तम पद प्रधान होता है।
3. कर्मधारय समास प्रथम पद विशेषण और दूसरा विशेष्य होता है। या उपमेय उपमान का भाव होता है।
4. द्विगु समास – प्रथम पद संख्यावाचक।
5. द्वन्द्व समास – दोनों पद प्रधान होते हैं और समुच्चय बोधक शब्द से जुड़े होते हैं।
6. बहुब्रीहि समास – दोनों पद को छोड़कर अन्य पद प्रधान होता है।

1. अव्ययी भाव समास

संधि और समास में अन्तर
सन्धि और समास में मख्य रूप से अन्तर यह है कि सन्धि दो वर्णों (अ. आ. इ, क, च आदि) में होती हैं, जबकि समास दो या दो से अधिक शब्दों में होता है। सन्धि में शब्दों को तोड़ने की क्रिया को ‘विच्छेद’ कहते हैं और समास में सामासिक पद को तोड़ने की क्रिया को ‘विग्रह’ कहते हैं। ..

2. तत्पुरुष समास
तत्पुरुष के भेद

(i) कर्म तत्पुरुष

(ii) करण तत्पुरुष

(iii) सम्प्रदान तत्पुरुष

(iv) अपादान तसुरुष

(v) संबंध तत्पुरुष

(vi) अधिकरण तत्पुरुष

एकाधिक शब्दों का लोप-

3. कर्मधारय समास

उपमेयोपमान कर्मधारय समस्त

4. द्विगु समास

5. द्वन्द्व समास

6. बहुब्रीहि समास

MP Board Class 12th Hindi Solutions

MP Board Class 12th Physics Solutions Chapter 4 गतिमान आवेश और चुम्बकत्व

गतिमान आवेश और चुम्बकत्व NCERT पाठ्यपुस्तक के अध्याय में पाठ्यनिहित प्रश्न एवं उनके उत्तर

प्रश्न 1.
तार की एक वृत्ताकार कुंडली में 100 फेरे हैं, प्रत्येक की त्रिज्या 8.0 सेमी है और इनमें 0.40 ऐम्पियर विद्युत धारा प्रवाहित हो रही है। कुंडली के केन्द्र पर चुम्बकीय क्षेत्र का परिमाण क्या है?
हल :
दिया है :
फेरों की संख्या N = 100,
कुंडली में धारा i = 0.40 ऐम्पियर
कुंडली की त्रिज्या r = 8.0 × 10^-2 मीटर,
केन्द्र पर चुम्बकीय क्षेत्र B= ?

= 3.14 × 10^-4 टेस्ला ।

प्रश्न 2.
एक लम्बे,सीधे तार में 35 ऐम्पियर विद्युत धारा प्रवाहित हो रही है। तार से 20 सेमी दूरी पर स्थित किसी बिन्दु पर चुम्बकीय क्षेत्र का परिमाण क्या है?
हल :
दिया है : सीधे तार में धारा i = 35 ऐम्पियर,
बिन्दु की तार से दूरी r = 0.20 मीटर
∴ लम्बे सीधे तार के कारण चम्बकीय क्षेत्र \(B=\frac{\mu_{0}}{2 \pi} \times \frac{i}{r}=\frac{4 \pi \times 10^{-7}}{2 \pi} \times \frac{35}{0.20}\)
= 3.5 × 10^-5 टेस्ला ।

प्रश्न 3.
क्षैतिज तल में रखे एक लम्बे सीधे तार में 50 ऐम्पियर विद्युत धारा उत्तर से दक्षिण की ओर प्रवाहित हो रही है। तार के पूर्व में 2.5 मीटर दूरी पर स्थित किसी बिन्दु पर चुम्बकीय क्षेत्र B का परिमाण और उसकी दिशा ज्ञात कीजिए।
हल :
दिया है :
तार में धारा i = 50 ऐम्पियर (उत्तर से दक्षिण),
तार से दूरी = 2.5 मीटर (पूर्व में)
तार के कारण चम्बकीय क्षेत्र B= \(\frac{\mu_{0}}{2 \pi} \times \frac{i}{r}=\frac{4 \pi \times 10^{-7}}{2 \pi} \times \frac{50}{2.5}\)
= 4 × 10^-6 टेस्ला ।
चुम्बकीय क्षेत्र की दिशा ऊर्ध्वाधरतः ऊपर की ओर होगी।

प्रश्न 4.
व्योमस्थ खिंचे क्षैतिज बिजली के तार में 90 ऐम्पियर विद्युत धारा पूर्व से पश्चिम की ओर प्रवाहित हो रही है। तार के 1.5 मीटर नीचे विद्युत धारा के कारण उत्पन्न चुम्बकीय क्षेत्र का परिमाण और दिशा क्या है?
हल :
तार में धारा i = 90 ऐम्पियर (पूर्व से पश्चिम), ..
तार से दूरी = 1.5 मीटर
तार के कारण चुम्बकीय क्षेत्र B= \(\frac{\mu_{0}}{2 \pi} \times \frac{i}{r}=\frac{4 \pi \times 10^{-7}}{2 \pi} \times \frac{90}{1.5}\)
= 1.2 × 10^-5 टेस्ला ।
चुम्बकीय क्षेत्र की दिशा क्षैतिजत: उत्तर से दक्षिण की ओर होगी।

प्रश्न 5.
एक तार जिसमें 8 ऐम्पियर विद्युत धारा प्रवाहित हो रही है, 0.15 टेस्ला के एकसमान चुम्बकीय क्षेत्र में, क्षेत्र से 30° का कोण बनाते हुए रखा है। इसकी एकांक लम्बाई पर लगने वाले बल का परिमाण और इसकी दिशा क्या है?
हल :
दिया है :
तार में धारा i = 8 ऐम्पियर,
चुम्बकीय क्षेत्र B = 0.15 टेस्ला,
तार व क्षेत्र के बीच कोण θ = 30°
∴ तार की एकांक लम्बाई पर बल F = ilB sin 30°
= 8 × 1 × 0.15 × \(\frac{1}{2}\)
= 0.6 न्यूटन-मीटर^-1।
बल की दिशा तार की लम्बाई तथा चुम्बकीय क्षेत्र की दिशा दोनों के लम्बवत होगी।

प्रश्न 6.
एक 3.0 सेमी लम्बा तार जिसमें 10 ऐम्पियर विद्युत धारा प्रवाहित हो रही है, एक परिनालिका के भीतर उसके अक्ष के लम्बवत् रखा है। परिनालिका के भीतर चुम्बकीय क्षेत्र का मान 0.27 टेस्ला है। तार पर लगने वाला चुम्बकीय बल क्या है?
हल :
तार की लम्बाई 1 = 3.0 × 10^-2 मीटर,
तार में धारा i = 10 ऐम्पियर
परिनालिका के भीतर चुम्बकीय क्षेत्र B= 0.27 टेस्ला
∵ परिनालिका के भीतर चुम्बकीय क्षेत्र उसकी अक्ष के अनुदिश होता है, अत: चुम्बकीय क्षेत्र तार की लम्बाई के लम्बवत् है।
∴ तार पर लाने वाला चुम्बकीय बल F = ilB sin 90°
= 10 × 3.0 × 10^-2 × 0.27
= 8.1 × 10^-2 न्यूटन।

प्रश्न 7.
एक-दूसरे से 4.0 सेमी की दूरी पर रखे दो लम्बे, सीधे, समान्तर तारों A एवं B से क्रमशः 8.0 ऐम्पियर एवं 5.0 ऐम्पियर की विद्युत धाराएँ एक ही दिशा में प्रवाहित हो रही हैं। तार A के 10 सेमी खण्ड पर बल का आकलन कीजिए।
हल :
तारों के बीच दूरी r= 4.0 × 10^-2 मीटर,
धाराएँ i₁ = 8.0 ऐम्पियर,
i₂ = 5.0 ऐम्पियर,
तार A की लम्बाई l = 0.10 मीटर

यह बल आकर्षण का होगा।

प्रश्न 8.
पास-पास फेरों वाली एक परिनालिका 80 सेमी लम्बी है और इसमें 5 परतें हैं जिनमें से प्रत्येक में 400 फेरे हैं। परिनालिका का व्यास 1.8 सेमी है। यदि इसमें 8.0 ऐम्पियर विद्युत धारा प्रवाहित हो रही है तो परिनालिका के भीतर केन्द्र के पास चुम्बकीय क्षेत्र \(\overrightarrow{\mathbf{B}}\) का परिमाण परिकलित कीजिए।
हल:
परिनालिका की लम्बाई l = 0.80 मीटर,
त्रिज्या r = 0.9 × 10^-2 मीटर
प्रवाहित धारा i = 8.0 ऐम्पियर,
कुल फेरे N = 5 × 400 = 2000
∴ एकांक लम्बाई में फेरों की संख्या \(n=\frac{N}{l}=\frac{2000}{0.8}\) = 2500 प्रति मीटर
∴ अक्ष पर केन्द्र के समीप चुम्बकीय क्षेत्र B= μ_oni = 4π × 10^-7 × 2500 × 8.0
= 8π × 10^-3 टेस्ला
= 2.5 × 10^-2 टेस्ला।

प्रश्न 9.
एक वर्गाकार कुंडली जिसकी प्रत्येक भुजा 10 सेमी है, में 20 फेरे हैं और उसमें 12 ऐम्पियर विद्युत धारा प्रवाहित हो रही है। कुंडली ऊर्ध्वाधरतः लटकी हुई है और इसके तल पर खींचा गया अभिलम्ब 0.80 टेस्ला के एकसमान चुम्बकीय क्षेत्र की दिशा से 30°का एक कोण बनाता है। कुंडली पर लगने वाले बलयुग्म आघूर्ण का परिमाण क्या है?
हल :
कुंडली में फेरे N = 20, धारा i = 12 ऐम्पियर, कुंडली की भुजा a = 0.1 मीटर .
B= 0.80 टेस्ला ,
θ = 30° बल-युग्म का आघूर्ण, t = ?
t = NiAB sin 30°
= Ni (a²) B sin 30°
= 20 × 12 x (0.1)² × 0.8 × \(\frac { 1 }{ 2 }\)
= 0.96 न्यूटन-मीटर।

प्रश्न 10.
दो चल कुंडली गैल्वेनोमीटर M₁ एवं M₂ के विवरण नीचे दिए गए हैं :
R₁ = 10Ω,
N₁ = 30,
A₁ = 3.6 × 10^-3 मीटर²
B₁ = 0.25 टेस्ला ,
R₂ = 14Ω,
N₂ = 42,
A = 1.8 × 10^-3 मीटर²
B₂ = 0.50 टेस्ला ।
(दोनों मीटरों के लिए स्प्रिंग नियतांक समान है)।
(a) M₂ एवं M₁ की धारा सुग्राहिताओं
(b) M₂ एवं M1 की वोल्टता सुग्राहिताओं का अनुपात ज्ञात कीजिए।
हल :
(a)

(b)

प्रश्न 11.
एक प्रकोष्ठ में 6.5 गाउस (1 गाउस= 10^-4 टेस्ला) का एकसमान चुम्बकीय क्षेत्र बनाए रखा गया है। इस चुम्बकीय क्षेत्र में एक इलेक्ट्रॉन 4.8 x 10⁶ मीटर-सेकण्ड^-1 के वेग से क्षेत्र के लम्बवत् भेजा गया है। व्याख्या कीजिए कि इस इलेक्ट्रॉन का पथ वृत्ताकार क्यों होगा? वृत्ताकार कक्षा की त्रिज्या ज्ञात कीजिए।
(e = 1.6 × 10^-19 कूलॉम, me = 9.1 × 10^-31 किग्रा)
हल :
दिया है :
B= 6.5 गाउस = 6.5 × 10^-4 टेस्ला,
इलेक्ट्रॉन का वेग υ = 4.8 × 10⁶ मीटर-सेकण्ड^-1
चूँकि इलेक्ट्रॉन चुम्बकीय क्षेत्र के लम्बवत् गतिमान है, अत: इलेक्ट्रॉन पर चुम्बकीय क्षेत्र के कारण बल सदैव इलेक्ट्रॉन के वेग के लम्बवत् दिशा में लगता है जो केवल इलेक्ट्रॉन की गति की दिशा में परिवर्तन करता है परन्तु वेग के परिणाम में कोई परिवर्तन उत्पन्न नहीं करता। इस कारण इलेक्ट्रॉन वृत्तीय पथ पर गति करता है।

प्रश्न 12.
प्रश्न 11 में, वृत्ताकार कक्षा में इलेक्ट्रॉन की परिक्रमण आवृत्ति प्राप्त कीजिए। क्या यह उत्तर इलेक्ट्रॉन के वेग पर निर्भर करता है? व्याख्या कीजिए।
हल :
∵ इलेक्ट्रॉन का वेग υ = 4.8 × 10⁶ मीटर-सेकण्ड^-1
तथा . कक्षा की त्रिज्या r = 4.2 × 10^-2 मीटर

∵ आवृत्ति का सूत्र इलेक्ट्रॉन की चाल से मुक्त है, अत: यह उत्तर इलेक्ट्रॉन के वेग पर निर्भर नहीं करता।

प्रश्न 13.
(a) 30 फेरों वाली एक वृत्ताकार कुंडली जिसकी त्रिज्या 8.0 सेमी है और जिसमें 6.0 ऐम्पियर विद्युत धारा प्रवाहित हो रही है, 1.0 टेस्ला के एकसमान क्षैतिज चुम्बकीय क्षेत्र में ऊर्ध्वाधरतः लटकी है। क्षेत्र रेखाएँ कुंडली के अभिलम्ब से 60° का कोण बनाती हैं। कुंडली को घूमने से रोकने के लिए जो प्रति आघूर्ण लगाया जाना चाहिए उसके परिमाण परिकलित कीजिए।
(b) यदि (a) में बतायी गई वृत्ताकार कुंडली को उसी क्षेत्रफल की अनियमित आकृति की समतलीय कुंडली से प्रतिस्थापित कर दिया जाए (शेष सभी विवरण अपरिवर्तित रहें.) तो क्या आपका उत्तर परिवर्तित हो जाएगा?
हल :
(a) कुंडली में फेरे N = 30, त्रिज्या r = 8.0 × 10^-2 मीटर, i = 6.0 ऐम्पियर
चुम्बकीय क्षेत्र B= 1.0 टेस्ला, θ = 60°
∴ कुंडली पर चुम्बकीय क्षेत्र के कारण बल-युग्म का आघूर्ण
t = NiAB sin 60°
= Ni (πr²) B sin 60°
= 30 × 6.0 × (3.14 × 64.0 x 10^-4) × 1.0 × \(\frac{\sqrt{3}}{2}\)
= 3.13 न्यूटन-मीटर।

स्पष्ट है कि कुंडली को घूमने से रोकने के लिए 3.13 न्यूटन-मीटर का बल-आघूर्ण विपरीत दिशा में लगाना होगा।

(b) नहीं, उत्तर में कोई परिवर्तन नहीं होगा। इसका कारण यह है कि बल-आघूर्ण (t = NiAB sin θ ) कुंडली के क्षेत्रफल A पर निर्भर करता है न कि उसके आकार पर।

प्रश्न 14.
दो समकेन्द्रिक वृत्ताकार कुंडलियाँ x और Y जिनकी त्रिज्याएँ क्रमशः 16 सेमी एवं 10 सेमी हैं, उत्तर-दक्षिण दिशा में समान ऊर्ध्वाधर तल में अवस्थित हैं। कुंडली X में 20 फेरे हैं और इसमें 16 ऐम्पियर विद्युत धारा प्रवाहित हो रही है, कुंडली Y में 25 फेरे हैं और इसमें 18 ऐम्पियर विद्युत धारा प्रवाहित हो रही है। पश्चिम की ओर मुख करके खड़ा एक प्रेक्षक देखता है कि X में धारा प्रवाह वामावर्त है जबकि Y में दक्षिणावर्त है। कुंडलियों के केन्द्र पर, उनमें प्रवाहित विद्युत धाराओं के कारण उत्पन्न कुल चुम्बकीय क्षेत्र का परिमाण एवं दिशा ज्ञात कीजिए।
हल :
दिया है : कुंडली X के लिए, r_X = 0.16 मीटर, N_X = 20, i_X = 16 ऐम्पियर
कुंडली Y के लिए, r_Y = 0.10 मीटर, N_Y = 25, i_Y = 18 ऐम्पियर

∵ B_X तथा B_Y परस्पर विपरीत हैं। अत: केन्द्र पर नेट चुम्बकीय क्षेत्र B= B_y – B_X
__= 9π × 10^-4 – 4π × 10^-4
= 5π × 10^-4 टेस्ला
= 1.5 × 10^-3 टेस्ला पश्चिम दिशा में। .

प्रश्न 15.
10 सेमी लम्बाई और 10^-3 मीटर² अनुप्रस्थ काट के एक क्षेत्र में 100 गाउस (1 गाउस= 10^-4 टेस्ला) का एकसमान चुम्बकीय क्षेत्र चाहिए, जिस तार से परिनालिका का निर्माण करना है उसमें अधिकतम 15A विद्युत धारा प्रवाहित हो सकती है और क्रोड पर अधिकतम 1000 फेरे प्रति मीटर लपेटे जा सकते हैं। इस उद्देश्य के लिए परिनालिका के निर्माण का विवरण सुझाइए। यह मान लीजिए कि क्रोड लोहचुम्बकीय नहीं है।
हल :
माना परिनालिका की एकांक लम्बाई में फेरों की संख्या n तथा उसमें प्रवाहित धारा i है तब उसकी अक्ष पर केन्द्रीय भाग में
चुम्बकीय क्षेत्र B= μ_oni ⇒ ni = \(\frac{B}{\mu_{0}}\)
∵ B= 100 × 10^-4 टेस्ला नियत है
तथा μ_o भी नियतांक है।
∴ दी गई परिनालिका के लिए ni = नियतांक
∵ इस प्रतिबन्ध में दो चर राशियाँ हैं, अतः हम किसी एक राशि को दी गई सीमाओं के अनुरूप स्वेच्छ मान देकर दूसरी राशि का चुनाव कर सकते हैं।
इससे स्पष्ट है कि अभीष्ट परिनालिका के बहुत से भिन्न-भिन्न विवरण सम्भव हैं।

हम जानते हैं कि परिनालिका की अक्ष पर उसके केन्द्रीय भाग में चुम्बकीय क्षेत्र लगभग एकसमान होता है। अत: दिया गया स्थान (10 सेमी लम्बा व 10^-3 मीटर² अनुप्रस्थ क्षेत्रफल वाला) परिनालिका की अक्ष के अनुदिश तथा केन्द्रीय भाग में होना चाहिए।
अतः परिनालिका की लम्बाई लगभग 50 सेमी से 100 सेमी के बीच (10 सेमी से काफी अधिक) होनी चाहिए तथा परिनालिका का अनुप्रस्थ क्षेत्रफल 10^-3 मीटर² से अधिक होना चाहिए।
माना परिनालिका की त्रिज्या r है, तब πr² > 10^-3
⇒ r² > \(\frac{10^{-3}}{3.14}\) = 3.18 x 10^-4
⇒ r > 1.78 × 10^-2 मीटर
या r > 1.78 सेमी
अत: हम परिनालिका की त्रिज्या 2 सेमी से अधिक (माना 3 सेमी) ले सकते हैं।
अतः परिनालिका का विवरण निम्नलिखित है :
लम्बाई l = 50 सेमी (लगभग),
फेरों की संख्या N = nl = 800 × 0.5 = 400 (लगभग),
त्रिज्या r = 3 सेमी (लगभग),
धारा i = 10 ऐम्पियर।

प्रश्न 16.
I धारावाही, N फेरों और R त्रिज्या वाली वृत्ताकार कुंडली के लिए, इसके अक्ष पर, केन्द्र से दूरी पर स्थित किसी बिन्दु पर चुम्बकीय क्षेत्र के लिए निम्नलिखित व्यंजक है –

(a) स्पष्ट कीजिए, इससे कुंडली के केन्द्र पर चुम्बकीय क्षेत्र के लिए सुपरिचित परिणाम कैसे प्राप्त किया जा . सकता है?
(b) बराबर त्रिज्या R एवं फेरों की संख्या N, वाली दो वृत्ताकार कुंडलियाँ एक-दूसरे से R दूरी पर एक-दूसरे के समान्तर, अक्ष मिलाकर रखी गई हैं। दोनों में समान विद्युत धारा एक ही दिशा में प्रवाहित हो रही है। दर्शाइए कि कुण्डलियों के अक्ष के लगभग मध्य-बिन्दु पर क्षेत्र, एक बहुत छोटी दूरी के लिए जो कि Rसे कम है, एकसमान है और इस क्षेत्र का लगभग मान निम्नलिखित है –
B = 0.70\(\frac{\mu_{0} N I}{R}\)
हल :
(a) दिए गए सूत्र में x = 0 रखने पर,

जो कि स्पष्टतया कुंडली के केन्द्र पर चुम्बकीय क्षेत्र का सूत्र है।
अतः दिए गए सूत्र से कुंडली के केन्द्र पर चुम्बकीय क्षेत्र ज्ञात करने के लिए x के स्थान पर शून्य रखना होगा।
(b) माना इस प्रकार की दो कुंडलियों के केन्द्रों को मिलाने वाली रेखा C₁C₂ का मध्य-बिन्दु C है तथा इससे d दूरी (दूरी d बहुत छोटी है) पर एक बिन्दु P स्थित है।
तब प्रथम कुंडली के लिए, x₁ = \(\frac { R }{ 2 }\) + d
तथा दूसरी कुंडली के लिए, x₂ =\(\frac { R }{ 2 }\) – d

∵ दोनों कुंडली पूर्णतः एक जैसी हैं तथा दोनों में धाराएँ भी एक ही दिशा में हैं, अत: बिन्दु P पर दोनों के कारण चुम्बकीय क्षेत्र एक ही दिशा में होंगे।

प्रश्न 17.
एक टोरॉइड के (अलौह चुम्बकीय) क्रोड की आन्तरिक त्रिज्या 25 सेमी और बाह्य त्रिज्या 26 सेमी है। इसके ऊपर किसी तार के 3500 फेरे लपेटे गए हैं। यदि तार में प्रवाहित विद्युत धारा 11 ऐम्पियर हो तो चुम्बकीय क्षेत्र का मान क्या होगा? (i) टोरॉइड के बाहर, (ii) टोरॉइड के क्रोड में, (iii) टोरॉइड द्वारा घिरी हुई खाली जगह में। हल :
दिया है : आन्तरिक त्रज्या r₁ = 0.25 मीटर,
बाह्य त्रिज्या r₂ = 0.26 मीटर
फेरों की संख्या N = 3500, धारा i = 11 ऐम्पियर
(i) टोरॉइड के बाहर चुम्बकीय क्षेत्र B= 0
(ii)

(iii) टोरॉइड द्वारा घेरे गए रिक्त स्थान में चुम्बकीय क्षेत्र B= 0.

प्रश्न 18.
निम्नलिखित प्रश्नों के उत्तर दीजिए-
(a) किसी प्रकोष्ठ में एक ऐसा चुम्बकीय क्षेत्र स्थापित किया गया है जिसका परिमाण तो एक बिन्दु पर बदलता है, पर दिशा निश्चित है ( पूर्व से पश्चिम)। इस प्रकोष्ठ में एक आवेशित कण प्रवेश करता है और अविचलित एक सरल रेखा में अचर वेग से चलता रहता है। आप कण के प्रारम्भिक वेग के बारे में क्या कह सकते हैं?
(b) एक आवेशित कण, एक ऐसे शक्तिशाली असमान चुम्बकीय क्षेत्र में प्रवेश करता है जिसका परिमाण एवं दिशा दोनों एक बिन्दु से दूसरे बिन्दु पर बदलते जाते हैं, एक जटिल पथ पर चलते हुए इसके बाहर आ जाता है। यदि यह मान लें कि चुम्बकीय क्षेत्र में इसका किसी भी दूसरे कण से कोई संघट्ट नहीं होता तो क्या इसकी अन्तिम चाल, प्रारम्भिक चाल के बराबर होगी?
(c) पश्चिम से पूर्व की ओर चलता हुआ एक इलेक्ट्रॉन एक ऐसे प्रकोष्ठ में प्रवेश करता है जिसमें उत्तर से दक्षिण दिशा की ओर एकसमान एक विद्युत क्षेत्र है। वह दिशा बताइए जिसमें एकसमान चुम्बकीय क्षेत्र स्थापित किया जाए ताकि इलेक्ट्रॉन को अपने सरल रेखीय पथ से विचलित होने से रोका जा सके।
हल :
(a) ∵ आवेशित कण अविचलित सरल रेखीय गति करता है, इसका यह अर्थ है कि कण पर चुम्बकीय क्षेत्र के कारण कोई बल नहीं लगा है। इससे प्रदर्शित होता है कि कण का प्रारम्भिक वेग या तो चुम्बकीय क्षेत्र की दिशा में है अथवा उसके विपरीत है।

(b) हाँ, कण की अन्तिम चाल उसकी प्रारम्भिक चाल के बराबर होगी। इसका कारण यह है कि चुम्बकीय क्षेत्र के कारण गतिमान आवेश पर कार्यरत बल सदैव कण के वेग के लम्बवत् दिशा में लगता है जो केवल गति की दिशा को बदल सकता है परन्तु कण की चाल को नहीं।

(c) ∵ विद्युत क्षेत्र के कारण इलेक्ट्रॉन पर दक्षिण से उत्तर की ओर विद्युत बल F_e कार्य करेगा, जिसके कारण इलेक्ट्रॉन उत्तर दिशा की ओर विक्षेपित होने की प्रवृत्ति रखेगा। इलेक्ट्रॉन बिना विचलित हुए सरल रेखीय गति करे इसके लिए आवश्यक है कि चुम्बकीय क्षेत्र ऐसी दिशा में लगाया जाए कि चुम्बकीय क्षेत्र के कारण इलेक्ट्रॉन पर उत्तर से दक्षिण दिशा की ओर चुम्बकीय बल कार्य करे। इसके लिए फ्लेमिंग के बाएँ हाथ के नियम से चुम्बकीय क्षेत्र ऊर्ध्वाधरत: नीचे की ओर लगाना चाहिए।

प्रश्न 19.
ऊष्मित कैथोड से उत्सर्जित और 2.0 किलोवोल्ट के विभवान्तर पर त्वरित एक इलेक्ट्रॉन 0.15 टेस्ला के एकसमान चुम्बकीय क्षेत्र में प्रवेश करता है। इलेक्ट्रॉन का गमन पथ ज्ञात कीजिए यदि चुम्बकीय क्षेत्र (a) प्रारम्भिक वेग के लम्बवत् है, (b) प्रारम्भिक वेग की दिशा से 30° का कोण बनाता है।
हल :
माना इलेक्ट्रॉन का वेग υ है, तब

(a) ∵ इलेक्ट्रॉन का वेग चुम्बकीय क्षेत्र के लम्बवत् है, अतः इस दशा में इलेक्ट्रॉन का पथ वृत्ताकार होगा।

(b) ∵ इलेक्ट्रॉन का वेग चुम्बकीय क्षेत्र के लम्बवत् नहीं है। अतः इस दशा में इलेक्ट्रॉन का पथ कुंडलिनीय (सर्पिलाकार) होगा। चुम्बकीय क्षेत्र के लम्ब दिशा में इलेक्ट्रॉन के वेग का वियोजित घटक

प्रश्न 20.
प्रश्न 16 में वर्णित हेल्महोल्ट्ज कुंडलियों का उपयोग करके किसी लघुक्षेत्र में 0.75 टेस्ला का एकसमान चुम्बकीय क्षेत्र स्थापित किया है। इसी क्षेत्र में कोई एकसमान स्थिर विद्युत क्षेत्र कुंडलियों के उभयनिष्ठ अक्ष के लम्बवत् लगाया जाता है। (एक ही प्रकार के) आवेशित कणों का 15 किलोवोल्ट विभवान्तर पर त्वरित एक संकीर्ण किरण पुंज इस क्षेत्र में दोनों कुंडलियों के अक्ष तथा स्थिर विद्युत क्षेत्र की लम्बवत् दिशा के अनुदिश प्रवेश करता है। यदि यह किरण पुंज 9.0 x 10^-5 वोल्ट मीटर^-1, स्थिर विद्युत क्षेत्र में अविक्षेपित रहता है तो यह अनुमान लगाइए कि किरण पुंज में कौन-से कण हैं। यह स्पष्ट कीजिए कि यह उत्तर एकमात्र उत्तर क्यों नहीं है?
हल :
दिया है : B = 0.75 टेस्ला; E = 9.0 × 10^-5 वोल्ट/मीटर^-1, V = 15 × 10³ वोल्ट
माना कण का द्रव्यमान m, वेग v तथा आवेश q है तब कण की

विद्युत क्षेत्र के कारण कण पर बल F_e = qE
तथा कण पर चुम्बकीय बल F_m = qυB sin 90° = qυ B
∵ दोनों क्षेत्रों से कण अविचलित गुजरता है, अतः कण पर कार्यरत दोनों बल परिमाण में बराबर व दिशा में विपरीत होंगे।
∴ qυB=qE

हम जानते हैं कि प्रोटॉन के लिए \(\frac{q}{m}\) का मान 9.6 x 10⁷ कूलॉम/किग्रा होता है जबकि दिए गए कणों के लिए \(\frac{q}{m}\) के मान का आधा है। इससे ज्ञात होता है कि इस कण का द्रव्यमान प्रोटॉन के द्रव्यमान का दोगुना होना चाहिए। अत: किरण पुंज में ड्यूटीरियम के आयन उपस्थित हो सकते हैं।

परन्तु ड्यूटीरियम ही एकमात्र ऐसा कण नहीं है जिसके लिए \(\frac{q}{m}\) का मान 4.8 x 10^-13 कूलॉम/किग्रा है। द्विआयनित हीलियम परमाणु (x-कण या हीलियम नाभिक He²⁺) के लिए \(\frac{2e}{2m}\) तथा त्रिआयनित लीथियम परमाणु (Li³⁺ ) के लिए \(\frac{3e}{3m}\) के लिए भी \(\frac{2e}{2m}\) का मान यही रहता है।

प्रश्न 21.
एक सीधी, क्षैतिज चालक छड़ जिसकी लम्बाई 0.45 मीटर एवं द्रव्यमान 60 ग्राम है इसके सिरों पर जुड़े दो ऊर्ध्वाधर तारों पर लटकी हुई है। तारों से होकर छड़ में 5.0 ऐम्पियर विद्युत धारा प्रवाहित हो रही है।
(a) चालक के लम्बवत् कितना चुम्बकीय क्षेत्र लगाया जाए कि तारों में तनाव शून्य हो जाए।
(b) चुम्बकीय क्षेत्र की दिशा यथावत् रखते हुए यदि विद्युत धारा की दिशा उत्क्रमित कर दी जाए तो तारों में कुल आवेश कितना होगा? (तारों के द्रव्यमान की उपेक्षा कीजिए।) (g = 9.8 मीटर सेकण्ड^-2)
हल :
छड़ की लम्बाई l = 0.45 मीटर व द्रव्यमान m = 0.06 किग्रा, तार में धारा i = 5.0 ऐम्पियर
(a) तारों में तनाव शून्य करने के लिए आवश्यक है कि चुम्बकीय क्षेत्र के कारण छड़ पर बल उसके भार के बराबर व विपरीत हो।
अतः ilB sin 90° = mg
⇒ \(B=\frac{m g}{i l}=\frac{0.06 \times 9.8}{5.0 \times 0.45}\) = 0.26 टेस्ला ।

(b) यदि धारा की दिशा बदल दी जाए तो चुम्बकीय बल तथा छड़ का भार दोनों एक ही दिशा में हो जाएँगे।
इस स्थिति में, तारों का तनाव = mg + ilB sin 90°
= mg + mg = 2mg (∵ प्रथम दशा से, ilB sin 90° = mg)
= 2 × 0.06 × 9.8= 1.176
= 1.18 न्यूटन।

प्रश्न 22.
एक स्वचालित वाहन की बैटरी से इसकी चालन मोटर को जोड़ने वाले तारों में 300 ऐम्पियर विद्यत धारा (अल्प काल के लिए) प्रवाहित होती है। तारों के बीच प्रति एकांक लम्बाई पर कितना बल लगता है यदि इनकी लम्बाई 70 सेमी एवं बीच की दूरी 1.5 सेमी हो। यह बल आकर्षण बल है या प्रतिकर्षण बल?
हल :
दिया है : तारों में धारा i₁ = i₂ = 300 ऐम्पियर,
बीच की दूरी r = 1.5 × 10^-2 मीटर
तारों की लम्बाई = 70 सेमी

= 1.2 न्यूटन-मीटर^-1।
चूँकि तारों में धारा विपरीत दिशा में प्रवाहित होती है, अतः यह बल प्रतिकर्षण का होगा।

प्रश्न 23.
1.5 टेस्ला का एकसमान चुम्बकीय क्षेत्र, 10.0 सेमी त्रिज्या के बेलनाकार क्षेत्र में विद्यमान है। इसकी दिशा अक्ष के समान्तर पूर्व से पश्चिम की ओर है। एक तार जिसमें 7.0 ऐम्पियर विद्युत धारा प्रवाहित हो रही है। इस क्षेत्र में होकर उत्तर से दक्षिण की ओर गुजरती है। तार पर लगने वाले बल का परिमाण और दिशा क्या है, यदि
(a) तार अक्ष को काटता हो
(b) तार N-S दिशा से घुमाकर उत्तर-पूर्व, उत्तर-पश्चिम दिशा में कर दिए जाए,
(c) N-S दिशा में रखते हुए ही तार को अक्ष से 6.0 सेमी नीचे उतार दिया जाए।
हल :
दिया है : B= 1.5 टेस्ला ,
क्षेत्र की त्रिज्या = 10.0 सेमी,
तार में धारा i = 7.0 ऐम्पियर

(a) इस दशा में तार की l = 2r = 0.20 मीटर लम्बाई चुम्बकीय क्षेत्र से गुजरेगी।

चूँकि क्षेत्र तार की लम्बाई के लम्बवत् है,
∴ तार पर बल F = ilB sin 90°
= 7.0 × 0.20 × 1.5 × 1
= 2.1न्यूटन।
बल की दिशा ऊर्ध्वाधरतः नीचे की ओर होगी।

(b) इस दशा में तार की लम्बाई चुम्बकीय क्षेत्र की दिशा से 45° का कोण बनाएगी।
माना,इस दशा में तार की l₁ लम्बाई चुम्बकीय क्षेत्र में गुजरती है, तब
sin 45° =\(\frac{2 r}{l_{1}}\) ⇒ l₁ =\(\frac{2 r}{\sin 45^{\circ}}=l \sqrt{2}\)
∴ तार पर बल F = il₁B sin 45°
\(=i l \sqrt{2} B \times \frac{1}{\sqrt{2}}\) = iBl
= 2.1न्यूटन (ऊर्ध्वाधर नीचे की ओर )।

(c) माना इस दशा में तार की l₂ (लम्बाई) (l₂ = AB) चुम्बकीय क्षेत्र से गुजरती है।
ΔOAC में, ∠OCA = 90°
∴ AC² = OA² – OC²
= 10² -6² = 64 ⇒ AC = 8 सेमी
∴ l₂ = AB = 2 AC = 16 सेमी
= 0.16 मीटर
∴ तार पर बल F = il₂B sin 90°
= 7.0 × 0.16 × 1.5 = 1.68 न्यूटन (ऊर्ध्वाधर नीचे की ओर)।

प्रश्न 24.
धनात्मक z-दिशा में 3000 गॉस का एक एकसमान चुम्बकीय-क्षेत्र लगाया गया है। एक आयताकार लूप जिसकी भुजाएँ 10 सेमी एवं 5 सेमी और जिसमें 12 ऐम्पियर धारा प्रवाहित हो रही है, इस क्षेत्र में रखा है। चित्र-4.5 में दिखायी गई लूप की विभिन्न स्थितियों में इस पर लगने वाला बल-युग्म आघूर्ण क्या है? हर स्थिति में बल क्या है? स्थायी सन्तुलन वाली स्थिति कौन-सी है?

हल :
दिया है : B= 3000 गाउस = 0.3 टेस्ला, a = 0.1 मीटर, b = 0.05 मीटर, i = 12 ऐम्पियर
कुंडली का क्षेत्रफल A = ab = 0.1 मीटर × 0.05 मीटर = 5 × 10^-3 मीटर²
(a), (b), (c), (d) प्रत्येक दशा में कुंडली के तल पर अभिलम्ब, चुम्बकीय क्षेत्र के लम्बवत् है। अत: प्रत्येक दशा में बल-युग्म का आघूर्ण t = iAB sin 90° .
= 12 × 5 × 10^-3 × 0.3 × 1
= 1.8 × 10^-2 न्यूटन-मीटर।
प्रत्येक दशा में बल शून्य है क्योंकि एकसमान चुम्बकीय क्षेत्र में रखे धारा लूप पर बल-युग्म कार्य करता है परन्तु बल नहीं।
(a) t = 1.8 × 10^-2 न्यूटन-मीटर ऋण Y-अक्ष की दिशा में तथा बल शून्य है।
(b) t = 1.8 × 10^-2 न्यूटन-मीटर ऋण Y-अक्ष की दिशा में तथा बल शून्य है।
(c) t = 1.8 × 10^-2 न्यूटन-मीटर ऋण X-अक्ष की दिशा में तथा बल शून्य है।
(d) t= 1.8 × 10^-2 न्यूटन-मीटर तथा बल शून्य है।
(e) तथा (f) दोनों स्थितियों में कुंडली के तल पर अभिलम्ब चुम्बकीय क्षेत्र के अनुदिश है अतः
t = iAB sin 0° = 0 .
अत: इन दोनों दशाओं में बल-आघूर्ण व बल दोनों शून्य हैं। यह स्थितियाँ सन्तुलन की स्थायी अवस्था को दर्शाती हैं।

प्रश्न 25.
एक वृत्ताकार कुंडली जिसमें 20 फेरे हैं और जिसकी त्रिज्या 10 सेमी है, एकसमान चुम्बकीय क्षेत्र में रखी है जिसका परिमाण 0.10 टेस्ला है और जो कुंडली के तल के लम्बवत् है। यदि कुंडली में 5.0 ऐम्पियर विद्युत धारा प्रवाहित हो रही हो, तो
(a) कुंडली पर लगने वाला कुल बलयुग्म आघूर्ण क्या है?
(b) कुंडली पर लगने वाला कुल परिणामी बल क्या है?
(c) चुम्बकीय क्षेत्र के कारण कुंडली के प्रत्येक इलेक्ट्रॉन पर लगने वाला कुल औसत बल क्या है?
(कुंडली 10^-5 मीटर² अनुप्रस्थ क्षेत्र वाले ताँबे के तार से बनी है, और ताँबे में मुक्त इलेक्ट्रॉन घनत्व 10²⁹ मीटर^-3 दिया गया है।)
हल:
फेरे N = 20, i = 5.0 ऐम्पियर, r = 0.10 मीटर, B= 0.10 टेस्ला
इलेक्ट्रॉन घनत्व n = 10²⁹ मीटर^-3 ,
तार का अनुप्रस्थ क्षेत्रफल A = 10^-5 मीटर²

(a) ∵ कुंडली का तल चुम्बकीय क्षेत्र के लम्बवत् है, अत: कुंडली के तल पर अभिलम्ब व चुम्बकीय क्षेत्र के बीच का कोण शून्य है (θ = 0°)
बल आधूर्ण t = NiAB sin 0° = 0
(b) कुंडली पर नेट बल भी शून्य है।
(c) यदि इलेक्ट्रॉनों का अपवाह वेग υ_d है तो

प्रश्न 26.
एक परिनालिका जो 60 सेमी लम्बी है, जिसकी त्रिज्या 4.0 सेमी है और जिसमें 300 फेरों वाली 3 परतें लपेटी गई हैं। इसके भीतर एक 2.0 सेमी लम्बा, 2.5 ग्राम द्रव्यमान का तार इसके ( केन्द्र के निकट) अक्ष के लम्बवत् रखा है। तार एवं परिनालिका का अक्ष दोनों क्षैतिज तल में हैं। तार को परिनालिका के समान्तर दो वाही संयोजकों द्वारा एक बाह्य बैटरी से जोड़ा गया है जो इसमें 6.0 ऐम्पियर विद्युत धारा प्रदान करती है। किस मान की विद्युत धारा (परिवहन की उचित दिशा के साथ) इस परिनालिका के फेरों में प्रवाहित होने वाले तार का भार संभाल सकेगी? (g = 9.8 मीटर सेकण्ड^-2)
हल :
परिनालिका की लम्बाई l = 0.6 मीटर,
त्रिज्या = 4.0 सेमी,
फेरे N = 300 × 3,
तार की लम्बाई L = 2.0 × 10^-2 मीटर,
द्रव्यमान m = 2.5 × 10^-3 किग्रा,
धारा I = 6.0 ऐम्पियर
माना परिनालिका में प्रवाहित धारा =i
तब परिनालिका के अक्ष पर केन्द्रीय भाग में चुम्बकीय क्षेत्र

∵ तार में धारा की दिशा ज्ञात नहीं है, अत: परिनालिका में धारा की दिशा बता पाना सम्भव नहीं है।

प्रश्न 27.
किसी गैल्वेनोमीटर की कुंडली का प्रतिरोध 12Ω है। 4 मिलीऐम्पियर की विद्युत धारा प्रवाहित होने पर यह पूर्ण स्केल विक्षेप दर्शाता है। आप इस गैल्वेनोमीटर को 0 से 18 वोल्ट परास वाले वोल्टमीटर में कैसे रूपान्तरित करेंगे?
हल :
दिया है : G = 12Ω, i_g= 4 मिलीऐम्पियर = 4 × 10^-3 ऐम्पियर
0 से V (V = 18 वोल्ट) वोल्ट परास के वोल्टमीटर में बदलने के लिए गैल्वेनोमीटर के श्रेणीक्रम में एक उच्च प्रतिरोध R जोड़ना होगा, जहाँ
\(\frac{V}{R+G}=i_{g} R+G = \frac{V}{i_{g}}\)
\(R=\frac{V}{i_{g}}-G=\frac{18}{4 \times 10^{-3}}-12=4488 \Omega\)
अत: गैल्वेनोमीटर के श्रेणीक्रम में 44882 का प्रतिरोध जोड़ना होगा।

प्रश्न 28.
किसी गैल्वेनोमीटर की कुंडली का प्रतिरोध 15 2 है। 4 मिली ऐम्पियर की विद्युत धारा प्रवाहित होने पर यह पूर्णस्केल विक्षेप दर्शाता है। आप इस गैल्वेनोमीटर को 0 से 6 ऐम्पियर परास वाले अमीटर में कैसे रूपान्तरित करेंगे?
हल : दिया है : G = 15Ω, i_g = 4 मिलीऐम्पियर = 4.0 × 10^-3 ऐम्पियर, i = 6 ऐम्पियर
गैल्वेनोमीटर को 0 से i ऐम्पियर धारा परास वाले अमीटर में बदलने के लिए इसके पार्श्वक्रम में एक सूक्ष्म प्रतिरोध S (शण्ट) जोड़ना होगा, जहाँ .

अत: इसके समान्तर क्रम में 10 m2 का प्रतिरोध जोड़ना होगा।

गतिमान आवेश और चुम्बकत्व NCERT भौतिक विज्ञान प्रश्न प्रदर्शिका (Physics Exemplar Q Problems) पुस्तक से चयनित महत्त्वपूर्ण प्रश्नों के हल

गतिमान आवेश और चुम्बकत्व बहुविकल्पीय प्रश्नोत्तर

प्रश्न 1.
बायो-सेवर्ट नियम इंगित करता है कि । वेग से गतिमान इलेक्ट्रॉनों द्वारा चुम्बकीय क्षेत्र Bइस प्रकार होता है कि –
(a) \(\overrightarrow{\mathrm{B}} \perp \vec{v}\)
(b) \(\overrightarrow{\mathrm{B}} \| \vec{v}\)
(c) यह व्युत्क्रम घन नियम का पालन करता है
(d) यह प्रेक्षण बिन्दु और इलेक्ट्रॉनों को मिलाने वाली रेखा के अनुदिश होता है।
उत्तर :
(a) \(\overrightarrow{\mathrm{B}} \perp \vec{v}\)

प्रश्न 2.
R त्रिज्या का कोई धारावाही वृत्ताकार लूप x-y तल में इस प्रकार रखा है कि उसका केन्द्र मूलबिन्दु पर हो। इसका वह अर्द्धभाग जिसके लिए x> 0 है, अब इस प्रकार मोड़ दिया गया है कि यह y-2 तल में रहे –
(a) अब चुम्बकीय-आघूर्ण का परिमाण घट जाता है
(b) चुम्बकीय-आघूर्ण परिवर्तित नहीं होता
(c) (0, 0, Z); Z>> R पर B का परिमाण बढ़ जाता है
(d) (0, 0, Z); Z >> R पर B का परिमाण अपरिवर्तित रहता है।
उत्तर :
(a) अब चुम्बकीय-आघूर्ण का परिमाण घट जाता है

प्रश्न 3.
एक इलेक्ट्रॉन को किसी लम्बी धारावाही परिनलिका के अक्ष के अनुदिश एकसमान वेग से प्रक्षेपित किया जाता है। निम्नलिखित में कौन सा प्रकथन सत्य है
(a) इलेक्ट्रॉन अक्ष के अनुदिश त्वरित होगा
(b) अक्ष के परित: इलेक्ट्रॉन का पथ वृत्ताकार होगा
(c) इलेक्ट्रॉन अक्ष से 45° पर बल अनुभव करेगा और इस प्रकार कुंडलिनी पथ पर गमन करेगा
(d) इलेक्ट्रॉन परिनालिका के अक्ष के अनुदिश एकसमान वेग से गति करता रहेगा।
उत्तर :
(d) इलेक्ट्रॉन परिनालिका के अक्ष के अनुदिश एकसमान वेग से गति करता रहेगा।

प्रश्न 4.
साइक्लोट्रॉन में कोई आवेशित कण –
(a) सदैव त्वरित होता है ।
(b) चुम्बकीय क्षेत्र के कारण दोनों ‘डी’ के बीच के अन्तराल में त्वरित होता है
(c) की चाल ‘डी’ में बढ़ जाती है
(d) की चाल ‘डी’ में मन्द हो जाती तथा दोनों ‘डी’ के बीच बढ़ जाती है।
उत्तर :
(a) सदैव त्वरित होता है ।

प्रश्न 5.
चुम्बकीय-आघूर्ण M का कोई विद्युतवाही वृत्ताकार लूप, किसी यादृच्छिक दिग्विन्यास में किसी बाह्य चुम्बकीय क्षेत्र में स्थित है। लूप को इसके तल के लम्बवत् अक्ष के परितः 30° पर घूर्णन कराने में किया गया कार्य है –
(a) MB :
(b) \(\sqrt{3} \frac{M B}{2}\)
(c) \(\frac{M B}{2}\)
(d) शून्य।
उत्तर :
(d) शून्य।

गतिमान आवेश और चुम्बकत्व अति लघु उत्तरीय प्रश्नोत्तर

प्रश्न 1.
यह सत्यापित कीजिए कि साइक्लोट्रॉन आवृत्ति \(\omega=\frac{e B}{m}\) की सही विमाएँ [T^-1] हैं।
उत्तर :
साइक्लोट्रॉन में चुम्बकीय क्षेत्र के लम्बवत् गति करते समय आवेशित कण वृत्ताकार पथ पर गति करता है, जिसके लिए आवश्यक अभिकेन्द्र बल, चुम्बकीय बल से प्राप्त होता है। अतः

प्रश्न 2.
यह दर्शाइए कि ऐसा बल जो कोई प्रभावी कार्य नहीं करता वेग-निर्भर बल होना चाहिए।
उत्तर :
बल कोई प्रभावी कार्य नहीं कर रहा है, अतः

प्रश्न 3.
साइक्लोट्रॉन में यदि रेडियो आवृत्ति (rf) वैद्युत क्षेत्र की आवृत्ति की दो गुनी हो जाए, तो उसमें किसी आवेशित कण की गति का वर्णन कीजिए।
उत्तर :
रेडियो आवृत्ति के दो गुनी हो जाने पर कण एकान्तर क्रम में त्वरित एवं मन्दित गति करेगा तथा दोनों डी में कण के पथ की त्रिज्या अपरिवर्तित रहेगी।

गतिमान आवेश और चुम्बकत्व आंकिक प्रश्नोत्तर

प्रश्न 1.
चित्र में दर्शाए गए गैल्वेनोमीटर परिपथ का उपयोग करके बहुपरिसरीय वोल्टमीटर की रचना की जा सकती है। हम एक ऐसे वोल्टमीटर की रचना करना चाहते हैं, जो 2 वोल्ट, 20 वोल्ट तथा 200 वोल्ट माप सके तथा 10Ω प्रतिरोध के ऐसे गैल्वेनोमीटर से बना हो जिसमें 1 मिलीऐम्पियर धारा से अधिकतम विक्षेप उत्पन्न होता है। इसके लिए उपयोग किए जाने वाले R₁, R₂ तथा R₃ के मान ज्ञात कीजिए।

हल :
गैल्वोनोमीटर को वोल्टमीटर में परिवर्तित करने के लिए
V = i_G (G + R)
जहाँ i_G = 1 मिलीऐम्पियर = 10^-3 ऐम्पियर
तथा G = 10Ω
(i) 0 से 2 वोल्ट परिसर के लिए, 2 = 10^-3 (10 + R₁)
या 2000 = 10 + R₁.
या R₁= 1990Ω

(ii) 0 से 20 वोल्ट परिसर के लिए, 20 = 10^-3 (10+ R + Ra)
या 20,000 = 10 + R₁ + R₂
या 19990 = R₁ + R₂
या R₂ = 19990 – 1990 = 18,000Ω = 18 kΩ

(iii) 0 से 200 वोल्ट परिसर के लिए, 200 = 10^-3 (10 + R₁ + R₂ + R₃ )
200000 = 10 + R₁ + R₂ + R₃
199990 = 1990 + 18000+ R₃
या R₃ = 199990 – 19990
= 180000Ω= 180 kΩ

प्रश्न 2.
कोई लम्बा सीधा तार जिसमें 25 ऐम्पियर धारा प्रवाहित हो रही है। चित्र में दर्शाइए अनुसार किसी मेज पर रखा है। 1 मीटर लम्बा 2.5 ग्राम द्रव्यमान का कोई अन्य तार PQ है जिसमें विपरीत दिशा में इतनी ही धारा प्रवाहित हो रही है। तार PQ ऊपर अथवा नीचे सरकने के लिए स्वतन्त्र है। तार PQ किस ऊँचाई तक ऊपर उठेगा?

हल :
माना तार PQ, h ऊँचाई तक ऊपर उठता है।
मेज पर रखे धारावाही तार के कारण h ऊँचाई पर उत्पन्न चुम्बकीय क्षेत्र,
\(B=\frac{\mu_{0}}{2 \pi} \cdot \frac{I}{h}\)
तार PQ पर कार्यरत चुम्बकीय बल F = BIl sin 90° = BIL
तार PQ पर नीचे की ओर कार्यरत तार का भार = mg
सन्तुलन की स्थिति में, BIl = mg

प्रश्न 3.
12 a लम्बाई.तथा प्रतिरोध का कोई एकसमान चालक तार एक धारावाही कुंडली के रूप में (i) भुजा a के समबाहु त्रिभुज (ii) भुजा a के वर्ग (iii) भुजा a के नियमित षट्भुज की आकृति में लपेटा गया है। कुंडली विभव स्रोतV से सम्बद्ध है। प्रत्येक प्रकरण में कुंडलियों का चुम्बकीय-आघूर्ण ज्ञात कीजिए।
हल :
तार की कुल लम्बाई = 12a
प्रतिरोध = R
विभवान्तर = V₀
प्रत्येक स्थिति में प्रवाहित धारा I=\(\frac{V_{0}}{R}\)

(i) a भुजा की समबाहु त्रिभुजाकार कुंडली में फेरों की संख्या (n₁) = \(\frac{12 a}{3 a}\) = 4
a भुजा की समबाहु त्रिभुजाकार कुंडली के अनुप्रस्थ काट का क्षेत्रफ (A) = \(\frac{\sqrt{3}}{4}\) a²

(ii) a भुजा की वर्गाकार कुंडली में फेरों की संख्या (n₂) = \(\frac{12 a}{4 a}\) = 3
कुंडली की अनुप्रस्थ काट का क्षेत्रफल (A₂) = a²
कुंडली का चुम्बकीय आघूर्ण (M₂) = n₂IA₂ =3 \(\times \frac{V_{0}}{R} \times a^{2}=\frac{3 V_{0} a^{2}}{R}\)
(iii) a भुजा की नियमित षट्भुजाकार कुंडली में फेरों की संख्या (n₃) = \(\frac{12 a}{6 a}\) = 2

प्रश्न 4.
चित्र में दर्शाए गए गैल्वेनोमीटर परिपथ का उपयोग करके बहपरिसरीय धारामापियों की रचना की जा सकती है। हम 10 mA, 100 mA तथा 1 A की धारा माप सकने वाले ऐसे धारामापी की रचना करना चाहते हैं जो 10Ω प्रतिरोध के ऐसे गैल्वेनोमीटर से बना हो जिसमें 1 mA धारा प्रवाहित होने पर अधिकतम विक्षेप होता है। इसके लिए उपयोग किए जाने वाले प्रतिरोधों S₁, S₂ तथा S₃ के मान ज्ञात कीजिए।

हल :
I_G = 1 mA = 10^-3A
तथा गैल्वेनोमीटर का प्रतिरोध (G) = 10Ω
गैल्वेनोमीटर को धारामापी में परिवर्तित करने के लिए उसके समान्तर क्रम में निम्न प्रतिरोध S लगाते हैं। अतः
I_G × G = (I – I_G) × S
(i) 10 मिली ऐम्पियर परिसर के लिए, I_G × G = (I₁-I_G) (S₁+S₂ +S₃)
अतः 10^-3 × 10 = (10 – 1) × 10^-3 (S₁ + S₂ + S₃)
अत: S₁ + S₂ + S₃ = \(\frac{10}{9}\) ……………………(1)

(ii) 100 मिलीऐम्पियर परिसर के लिए, I_G × G = (I₂ – I_G) (S₂ + S₃)
10^-3 × 100 = (100 – 1) × 10^-3 (S₂ + S₃)
या  S₂ + S₃ = \(\frac{10}{99}\)……………………(2)

(iii) 1 ऐम्पियर परिसर के लिए, . I_G × G = (I₃ – I_G) S₃
10^-3 × 10 = (1 – 1 × 10^-3) × S₃

MP Board Class 12th Physics Solutions