Strength of magnetic field is directly proportional to current. Strength of magnetic field is inversely proportional to radius of circular wire.

The ratio between the speed of light in medium to speed in a vacuum is the refractive index. When light travels in medium other than the vacuum, the atoms of that medium continually absorb and re-emit the particles of light, slowing down the speed light.

The formula of the refractive index is as follows:

n=c / v

Where,

n is the refractive index

c is the velocity of light in a vacuum ( 3 × 108 m/s)

v is the velocity of light in a substance

Electric motor: A motor is a device which converts electrical energy into mechanical energy.
Principle of motor : A motor works on the principle that when a rectangular coil is placed in a magnetic field and current is passed through it. A force acts on the coil which rotates it continuously.

1. When electric current is passed into the rectangular coil, this current produces a magnetic field around the coil.
2. The magnetic field of horse shoe-type magnet then interacts with the magnetic field of the coil and causes the coil to rotate continuously.
3. If ABCD is in horizontal position current from battery enters the coil through brush B _{ 1 }, and commutator half ring C:. The current flows in the direction ABCD
   and leaves via ring and brush B _{ 2 }
4. The direction of current is from A to B, the direction of current is from C to D. The force on side AB of the coil is in the downward direction. Whereas the force on the side CD of the coil is in the upward direction. ABCD rotate in anti-clockwise direction.
5. While rotating when the coil reaches vertical position then the brushes B _{ 1 } and B _{ 2 } will touch the gap between the commutator rings and current to the coil is cut off. But the coil does not stop rotating because it has already gained momentum.
6. The coil CD comes on the left side and AB comes to the right side. Again they come in contact with brush B _{ 1 } Current direction is reversed.
7. The reversing of current in the coil is repeated after every half rotation due to which the coil continue to rotate as long as current from the batter is passed through it. The rotating shaft of electric motor can drive a large number of machines which are connected to it.

AB= √(9-9)²+(6-0)² = 6
BC= √(-9-9)²+(6-6)² = 18
CD = √(-9+9)²+(0-6)² = 6
DA = √(-9-9)²+(0-0)² = 18
so,it's opposite sides are equal,hence it is rectangle.

Let the point be A(5,−6), B(−1,−4) and P(0,y)

Point P is on y−axis,hence its x co-ordinate is 0.So, it is of the form P(0,y)

Now, we have to find ratio.

Let the ratio be k:1

Hence m₁​=k,m_2​=1,x_1​=5,y_1​=−6,x₂​=−1,y_2​=−4,x=0,y=0

Using sections formula x= (m₁​x₂​+m₂​x₁​​)/m₁​+m_2​

⇒0=−k+5​/k+1

∴k=5

Again y=(m₁​y₂​+m_2​y₁​​)/m_1​+m_2​

=−4k−6​/ k+1 = (−20−6​)/ 6 for k=5

=−13​/3

Hence the coordiantes of point is P(0,−13​/3)

The French Revolution helped introduce nationalism in Europe, for it changed France's entire system of government, defined citizens' rights, and developed a set of national symbols. The Revolution also spread nationalism to other countries. ... After Napoleon's defeat, Europe reacted against nationalism for a while.

यौवन जिंदगी का सर्वाधिक मादक अवस्था होता है । इस अवस्था को भोग रहा युवक वर्ग ,केवल देश की शक्ति ही नहीं, बल्कि वहाँ की सांस्कृतिक आत्मा का प्रतीक भी होता है । अगर हम यह मानते हैं कि, यह संसार एक उद्यान है, तो ये नौजवान इस उद्यान की सुगंध हैं । युवा वर्ग किसी भी काल या देश का आईना होता है जिसमें हमें उस युग का भूत, वर्तमान और भविष्य , साफ़ दिखाई पड़ता है । इनमें इतना जोश रहता है कि ये किसी भी चुनौती को स्वीकारने के लिये तैयार रहते हैं । चाहे वह कुर्बानी ही क्यों न हो, नवयुवक अतीत का गौरव और भविष्य का कर्णधार होता है और इसी में यौवन की सच्ची सार्थकता भी है ।

हमारे दूसरे वर्ग, बूढ़े- बुजुर्ग जिनके बनाये ढ़ाँचे पर यह समाज खड़ा रहता आया है; उनका कर्त्तव्य बनता है कि इन नव युवकों के प्रति अपने हृदय में स्नेह और आदर की भावना रखें, साथ ही बर्जना भी । ऐसा नहीं होने पर, अच्छे-बुरे की पहचान उन्हें कैसे होगी ? आग मत छूओ, जल जावोगे; नहीं बताने से वे कैसे जानेंगे कि आग से क्या होता है ? माता-पिता को या समाज के बड़े-बुजुर्गों को भी, नव वर्ग के बताये रास्ते अगर सुगम हों, तो उन्हें झटपट स्वीकार कर उन रास्तों पर चलने की कोशिश करनी चाहिये ।

ऐसे आज 21वीं सदी की युवा शक्ति की सोच में,और पिछले सदियों के युवकों की सोच में जमीं-आसमां का फ़र्क आया है । आज के नव युवक , वे ढ़ेर सारी सुख-सुविधाओं के बीच जीवन व्यतीत करने की होड़ में अपने सांस्कृतिक तथा पारिवारिक मूल्यों और आंतरिक शांति को दावँ पर लगा रहे हैं । सफ़लता पाने की अंधी दौड़, जीवन शैली को इस कदर अस्त-व्यस्त और विकृत कर दिया है कि आधुनिकता के नाम पर पश्चिमी सभ्यता का अनुसरण ,उनके जीवन को बर्वाद कर दे रहा है । उनकी सहनशीलता खत्म होती जा रही है । युवकों के संयमहीन व्यवहार के लिए हमारे आज के नेता भी दोषी हैं । आरक्षण तथा धर्म-जाति के नाम पर इनका इस्तेमाल कर, इनकी भावनाओं को अपने उग्र भाषणों से भड़काते हैं और युवाओं की ऊर्जा का गलत प्रयोग कर अपने स्वार्थ की पूर्ति करते है ;जिसके फ़लस्वरूप आज युवा वर्ग भटक रहा है । धैर्य, नैतिकता, आदर्श जैसे शब्द उनसे दूर होते जा रहे हैं । पथभ्रष्ट और दिशाहीन युवक, एक स्वस्थ देश के लिए चिंता का विषय है । आज टेलीवीजन , जो घर-घर में पौ फ़टते ही अपराधी जगत का समाचार, लूट, व्यभिचार, चोरी का समाचार लेकर उपस्थित हो जाता है,या फ़िर गंदे अश्लील गानों को बजने छोड़ देता है । कोई अच्छा समाचार शायद ही देखने मिलता है । ये टेलीवीजन चैनल भी युवा वर्ग को भटकाने में अहम रोल निभा रहे हैं । दूसरी ओर इनकी इस दयनीय मनोवृति के लिये उनके माता-पिता व अभिभावक भी कम दोषी नहीं हैं । वे बच्चों की मानसिक क्षमता का आंकलन किये बिना उन्हें आई० ए० एस०, पी०सी० एस०, डाक्टर, वकील, ईंजीनियर आदि बनाने की चाह पाल बैठते हैं और जब बच्चों द्वारा उनकी यह चाहत पूरी नहीं होती है, तब उन्हें कोसने लगते हैं । जिससे बच्चों का मनोबल गिर जाता है । वे घर में तो चुपचाप होकर उनके गुस्से को बरदास्त कर लेते हैं; कोई वाद-विवाद में नहीं जाते हैं, यह सोचकर,कि माता-पिता को भविष्य के लिये और अधिक नाराज करना ठीक नहीं होगा । लेकिन ये युवक जब घर से बाहर निकलते हैं, तब बात-बात में अपने मित्रों, पास-पड़ोसी से झगड़ जाते हैं । इसलिये भलाई इसी में है कि बच्चों की मानसिक क्षमता के अनुसार ही माँ-बाप को अपनी अपेक्षा रखनी चाहिये । अन्यथा उनके व्यक्तित्व का संतुलित विकास नहीं हो पायेगा ; जो कि बच्चों के भविष्य के लिये बहुत हानिकर है ।

D-34

Ras Vihar

Dwarka

New Delhi

January 26, 2020

The Municipal Commissioner  

Municipal Corporation

New Delhi

Subject: Uncovered and broken manholes on the roads

Sir:

I am writing to your good-self to bring to your attention the inconvenience being faced by the residents of Ras Vihar. There are many open and broken manholes on the roads in our colony. These open manholes pose serious threats to the residents, especially during the rainy seasons. We have written many letters requesting the concerned authorities but to no avail. Owing to these manholes, everyday there is a mishap of some sort.  

I on behalf of the residents of the colony appeal to you to relieve us of the inconvenience we have been facing for so many weeks. Our children, elderly, and other people are getting hurt every day, not to mention the harassment we are constantly facing. Kindly either repair the manholes. I hope you will seriously look into the matter. Thanking you.

Yours truly,

Surekha  

The carbon dioxide gas enters the leaves of the plants through the stomata present on their surface.

19वीं शताब्दी में उदारवादी विचारधारा , राजनीतिक रूप से एक ऐसर सरकार पर जोर देता था जो सहमति से बनी हो । फ्रांसीसी क्रांति के बाद उदारवाद निंरकुश शासक और पादरीवर्ग के विशेषाधिकारों की समाप्ति , संविधान तथा संसदीय प्रतिनिधि सरकार का पक्षधर था ।

We ought to love our neighbours

The ideology of liberalism allied with Nationalism in the following ways: 

(i) Liberalism stood for freedom for the individual and equality of all before law. 

(ii) It emphasized on the concept of government by consent.

(iii) It stood for the end of autocracy and clerical privileges.

(iv) It believed in a constitution and representative government through Parliament. 

(v) It emphasized the inviolability of private property.

The term liberalism' comes from the Latin root liber which meant to be free.

1. In the political sense, liberalism stood for freedom for the individual and equality of all before the law. It emphasised on the end of aristocracy and clerical privileges, a constitution and representative government through parliament and the inviolability of private property, drawing its basic foundation from the French Revolution.
2. From the very beginning, universal suffrage i.e. voting rights were granted only to the property-owning men, excluding men without property and all women. However, throughout the nineteenth century and early twenties, many movements were organised demanding equal political rights.
3. In the economic sense, liberalism stood for the freedom of markets and the abolition of state-imposed restrictions on the movement of goods and capital. People often attempted to go beyond the state restrictions such as the formation of a customs union by Prussia in 1834 which abolished tariff barriers and no. of currencies from 30 to 2. The creation of railway networks further stimulated national unification and the wave of economic nationalism in all contributed towards strengthening wider national sentiments.

Food chain in the sea.   

(i) Initially, primary sector was the main economic activity.
(ii) Dueto improved methods of farming, productivity of agriculture sector increased. Therefore, more persons were taking up other activities like trading, transport, army, administration etc.
(iii) Secondary sector (or manufacturing sector) became the most important sector for production and employment, over a long period of time. This was a shift from primary to secondary sector as more and more factories were started.
(iv) In developed countries a further shift from secondary sector to tertiary sector is observed in past 100 years. Major portion of the working population is engaged in service sector.
In conclusion, in developed economies, tertiary sector has gained an important position.

The central idea around which the entire poem revolves is that only love, equality, mutual understanding and sympathy for one and all can help in establishing peace on the Earth. The poet mentions that both fire and ice are probable ends of this world. While he talks about how fire represents desire and can, therefore, be a cause of the end of the world, he also mentions ice in between to symbolize that the coldness and indifference towards one another will also be enough to end the world.