Experiment to produce induced EMF and Current

Description:
Consider a straight piece of wire of length in magnetic field of a permanent magnet . The wire is connected with a sensitive   galvanometer. so it forms a closed loop without battery.
Induced Current:
When we move the loop from left to right a current flow in the loop . The current stops when the loop stops to move. Now, if we move loop in opposite in direction current also in the reverse direction.

Induced Emf:
If we change the resistance of the loop by inserting different resistor in the loop and move it in uniform magnetic field with same velocity then the product of the induced current and resistance of the loop remain constant.

Conclusion:
Relative motion of the loop and the mognet produces Induced emf in the loop, In mf is produced Greater the rate of change of magnetic flux, larger is the alvanometariment we use a bar magnet and a coll to which a sensitive.

 Case- In 1:
 Induction due to Motion of Magnet) galvanometer is connected as shown in galvanometer en there is no relative motion between magnet and coll then shows no current.
Case- II :
When the b ote bar magnet is moved towards the coll,the magnetic flux changes and a current is Induced in the coll.
 Case- III :
When the bar magnet Is moved away from the coil, the magnetic flux changes and a current is Induced in the coil in opposite direction Alternate Method This experiment can also be performed by moving the coil towards or away from the magnet.
Experiment No.3:
induction due to Changing the Area of Coil) In this experiment we can produce the induced current by changing the area of coil in uniform magnetic field, as shown in figure When the coil is being distorted so as to reduce its. area an emf and hence current appears. The induced current disappears when there will be no change in area. When the distorted col comes to its original circular shape thereby increasing the area, the induced current is produced but opposite in direction This current lasts as long as the area is changing.

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In the Street of the Fruit Stalls

Description:
In the Street of the Fruit Stalls
Wicks balance flame, a dark dew falls
 In the street of the fruit stalls .
Melon, guava, mandarin,
Pyramid-piled like cannon balls
Glow red-hot, gold-hot, from within.
Dark children with a coin to spend
 Enter the lantern's orbit; find
Melon, guava, mandarin-
The moon compacted to a rind,
The sun in a pitted skin.
They take it, break it open, let
A gold or silver fountain wet
 Mouth, fingers, cheek, nose, chin:
Radiant as lanterns, they forget
The dark street I am standing in.

Theme:

This is a symbolic poem. The world is threatened with war. enjoy the poverty. But all these have failed to crush man's love for pleasure. Childre sweet spray of the juice forgetting all about the misery they live in Paraphrase It is evening time. I t is wet and dark. There is a street of fruit sellers where various fruit are piled up in a conical form. They reflect hot, red and golden colours which in dim lantern light look like bombs. Poor children come there with a coin and stand in the light of the lanterns. They look at melon, guava and other fruit. Their mouths water. They pick up a fruit and break it open. Juice comes out and pours itself into their mouths, and also sticks on their fingers and cheeks. They enjoy the fruit, and are least conscious of their surroundings.

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CHINA OF WAY TO PROGRESS

Description:
For twenty-two years China lay forgotten and was even confused with a small island one of its provinces and the flexile Chines countered by a Western curtain of rigid disregard. Then suddenly that one-fourth of , mankind enclosed in the world's third largest country was brought out of the memory 8nt attic, with a loud bang The Chinese may have introduced the smile policy, but the Occidentals certainly launched the warm hug. The crowd of official visitors to Peking, performing a devoted quasi-pilgrimage, is now more numerous than the battalions of traders who go twice yearly to the traditional Canton Fair. Seventy three year old Chou En-Lai will end up dislocating his right hand if he goes on shaking it at the present rate with delegations running into hundreds of people at a time, his eyes blinded by the constant flashing of the official souvenir photographers .The queue of countries on the waiting list to recognize the People's Republic of China is growing longer with the mounting awareness of the absurdity of the past oblivion or a political guilt complex for having kept China out of the UN for along time.

China is now the fashion:

China is now the fashion around the world, and in no uncertain terms Everywhere politicians of the most conservative and bourgeois kind are attempting to rebuild for themselves a compromised career by singing the praises of Mao Tse-Tung.

An Exemplary Social Experiment:
When confronting the enigma of the Chinese planet, too many Westerners have forgotten the Asiatic background and painful colonial history. But when the Cómunists came to power in 1949 the vast majority, of the country Artfeon as it had been doing for the past 2,000 years, in an early iron Age country. And on, countless occasions during our visits to the agricultural communes we were proudly told: "Here we didn't even have the life of the oxen and horses" Compared to China in 1949 Russia 1917 did not have the inheritance o fa century of a shattering multi-colonial experience   Russia never suffered China's Fate of such a sharp and pervasive Western impact that it was forced schizophrenia not just in terms of a split economy, but above all in terms of a split together with many other Asiatic civilizations into a kind of national culture and a split personality In China the individual has been rescued from the aftermath of this unfortunate heritage by the newfound companionship, common purpose and discipline of mass-organization. Just as the Vietnamese have withstood American technology so the ascetic militant Chinese have gone straight to the roots of the problems that have plagued Asian countries for thousands of years - the lack of food.

Day in the Life of a 16-year old:
How do the students live and what do they think individually? Despite having to use an interpreter I was able to find out. Here is the result of my interview with Je Wen-Siu, a sixteen-years old girl who lives in the workers' district of Peng Pu at Shanghai. She is a pupil in class 3 at the junior school She will shortly be taking her diploma. "How do you spend your day" "l get up at 6 o'clock in the morning, do a few chores in the house, have breakfast and go to school at 8. I finish at 11 o'clock. I go home and have lunch. At one thirty I'm back at school again until 3 o'clock. Then I go back home and work." "How much time do you spend on homework at home?" "Well actually I do my homework at school. At home I go through the lessons for about an hour. From 4 o'clock on I relax, reading the papers and listening to the radio." "What news are you most interested in?" "All political news which illustrate the national and international situation." "What do you do when you meet with your girl friends" I often go out with girls and boys of my age. We do some sports and often play ping-pong.
China future:

[03:57, 8/10/2018] Adnan Sami: There are two opposite worlds just as the two ways of considering China's future are opposite. One is the rigid world of figures and prospects based on economic thought throughout China, with the little Red Book. As for Western economic laws, the endless mass of 600 million people, who can be convinced. governed and directed facts as seen by the West. The other is the world of faith, of the development of Mac along the paths decided by the powers that be, might well overthrow the whole Reasoning with the dry yardstick of figures, the contribution of a dollar from each Chinese would

make roughly 800 million dollars and the contribution of a day's work from each person would mean two million extra labourers for one year without cost to the State. True, to increase by just one metre per head the availability of cloth for even as few as 700 million Chinese, you would need enough cloth to go round the world eighteen times while the purchase of a million and a half tons of grain is only sufficient to feed the Chinese population for 5 days. The fact remains that when the number is not simply a juxtaposition of persons, but a compact whole, then it tends to become "Power". When Mao says that it is the people, and not things, that are decisive, he is trying in fact to demonstrate that this concept apparently destroyed by modern technology is still a meaningful one.

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Petrol Engine and diesel engine

Description:
Although different engines may differ in their construct technology but they are based on the principle of a Can cycle. A typical four stroke petrol engine   also undergoes four successive processes in each cycle.

1. The cycle starts on the intake stroke in which piston.
 2. On the compression stroke, the inlet valve is closed and he mixture is compressed adiabatically by inwa
3.
On the power stroke, a spark fires the mixture causing a movement of the piston ng rapid increase in pressure and temperature. The burmi mixture expands adiabatically and forces the piston to move outward. This is the stroke which delivers power to crank shaft to drive the flywheels.
4. On the exhaust stroke, the outlet valves opens. The residual gases are expelled and piston moves inward .
The cycle then begins again. Most motorbikes have one cylinder engine but cars usually have four cylinders on the same crankshaft . The cylinders are timed to fire turn by turn in succession for a smooth running of the car. The actual efficiency of properly tuned engine is usually not more than 25 % to 30 % because of function and other heat losses .
 Diesel Engine :
No spark plug is needed in the diesel engine  Diesel is sprayed into the cylinder at maximum compression Because air is at very high temperature immediately after compression, the fuel mixture ignites on contact with the air in the cylinder and pushes the piston outward. The efficiency of in diesel engine is about 35 % to 40 % .

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Resonance

Description:

RESONANCE is a motion of a driven harmonic oscillator external driving force is periodic with a 7.8 striking phenomenon, known as resona e is a very arises if the phenomeno drivi period comparable to t amplitude of the imparable to the natural period of the oscillator uation, the driving force may be feeble, motion may become extra ordinarily e case of oscillating simple pendulum, if ma y become extra ordination In rg sh the pendulum whenever it comes in front o it is found that the amplitude steadily increases. 94 our mouth, it is fo trate this resonance effect, an apparatus is in.

Explanation:
A horizontal rod AB is supported by two strings Si and S2. Three pairs of pendulums aa, bb and cc are suspended to this rod. The length of each pair is the me but is different for different pairs. resonance of these pendulums, say c, is displaced in a direction perpendicular to the plane of the paper, then its resultant oscillatory m motion causes in rod AB a very slight disturbing motion, whose period is the same as that of c. Due to this slight motion of the rod, each of the remaining pendulums (aa bb',and cc') under go a slight periodic motion.

This causes the pendulum c, whose length and, hence, period is aes exactly the same as that of c, to oscillate back and forth with steadily increasing amplitude. However, the Al of the other pendulums remain small through n out the subsequent motions of c and c, because their Important   natural periods are not the same as that of the energy of the oscillation comes from the driving source. tor could be vill ng re force due to rod AB The energy of t At resonance ,the transfer of energy is maximum us resonance occurs when the frequency of the   periodic forced is equal to one of the natural frequency   of the forced or driven harmonic oscillator.


Advantages And Disadvantages of Resonance:

We come across many examples of resonance day life. A swing is a good example of mechanicals in every on resonance.It is like a pendulum with a single natural frequency resonance. It is like a pendulum with a single natural freque depending on its length. If a series of regular pushes are given to the swing, its motion can be built up enormously. If we pushes are given irregularly, the swing will hardly vibrate. The column of soldiers, while marching on a bridge of long span are advised to break their steps. Their rhythmic march might set up oscillations of dangerously large amplitude in the bridge structure. Tuning a radio is the best example of electrical resonance.

 When we turn the knob of a radio, to tune a station, we are changing the natural frequency of the electric circuit of the receiver, to make it equal to the transmission frequency of the radio station. When the two frequencies match, energy row due tron absorption is maximum and this is the only station we hear. es aves Another good example of resonance is the heating and cooking of food very efficiently and evenly by microwave oven . The waves produced in this type of oven have a wavelength of 12 cm at a frequency of 2450 MHz. At this frequency the waves are absorbed due to resonance by water and fat molecules in the food, heating them up and so cooking the food.

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Different Networks Models

Description:
two models of computer networks. These are as follows: There are .
1) Client-Server Model .
2) Peer-to-Peer Model etc.

1. Client-Server Model/Dedicated Server Network:
In client-server model, one or more computers work as servers and other computers easily. work as clients. The server computer controls the whole network. It is used to store data and programs to be shared among different computers in the network. It may also share a  attached with it. Server is more powerful computer than other computers in the network.It perform rms most of the processing in this network model.

Client-server model Some servers are called dedicated servers. A dedicated server is used to perform specific task. For example, file server is used to store and manage files. A print server is u to manage printers and printing tasks. Similarly, network server manages network resource.

Advantage and Disadvantage:

It reduces the volume of data traffic on the network   . It can use less powerful computers as clients because most of the processing is done by the server computer .
Disadvantages It is expensive model because server computers are costly The operations stop all over the network when server goes down.

Types no 2. Peer-to-Peer Model:
All computers in peer-to-peer model have same status. There is no server computer to control other computers. Each computer in this network can have access to devices and files on other computers.
Advantage :
Some important advantages of peer-to-peer model are as follows. .It is easy to setup. .It is easy to maintain. .It does not require expensive server computer. .It is suitable for small office of ten or less computers.

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Data Communication

Description:

Data communication is a process of transferring data electronically from one place to another. Data can be transferred by using different medium. The basic components of data communication are as follows:
1) .Message . 
2)Sender .
3)Receiver .
4) Transmission Medium
5) Encoder and Decoder

1) Figure: Data Communication

1)  Message:

The message is the data or information to be communicated. It may consist of text. umber, picture, sound, video or a combination of these.


2) Sender:

Sender is the device that sends the message. It is also called source or tr sender can be a computer, fax machine or mobile phone etc. The computer is usually ansmitter The used as sender in data communication systems.

3). Receiver:

It is also called sink. The receiver capable to accept the message. The receiver can be a computer, printer, fax machinight or mobile phone etc. A computer is usually used as receiver in data communication.
4). Transmission Medium :

Transmission medium is the path through which the messages are transferred. It b used to carry messages from one place to another. It is also called communication channel The transmission medium is a physical cable or wireless connection.

5.) Encoder and Decoder:

The encoder is a device that converts digital signals in a form that can pass through a Amplitud transmission medium. The decoder is a device that converts the encoded signals into digital form. The receiver can understand the digital form of message. Sender and receiver cannot communicate successfully without encoder and decoder.

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Leisure

Description:

What is this life if, full of care
We have no time to stand and stare?
 No time to stand beneath the boughs
And stare as long as sheep or cows:
 No time to see, in broad daylight,
 Streams full of stars, like skies at night:
No time to turn at Beauty's glance,
And watch her feet, how they can dance
No time to wait till her mouth can
 Enrich that smile, her eyes began?

 A poor life this if,full of care.
We have no time to stand and stare....

(William Henry Davies)

Theme:
The poem has based this poem on personal experience. He thinks that one is t with daily routine of life that most of the time the beauty and the busy in coping joys of life are ignored. time to enjoy and look at the wonders around us. He has music and smiles One has no mentioned the animals on the pastures, the stars in the sky, the around him. According to the poet's point of view, a man's life is so full of worries and care that he cannot even stand and look up at things as they are around him.

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A Sindhi Woman

Description:
 Bare foot, through the bazaar,
 And with the same undulant grace
 As the cloth blown back from her face,
 She glides with a stone jar
 High on her head
And not a ripple in her tread.
 Watching her cross erect
Stones, garbage, excrement and crumbs
 Of glass in the Karachi slums,
 I, with my stoop, reflect
 They stand most straight
 Who learn to walk beneath a weight.

 

Theme:
This poem is a tribute to a Work keeps a person strong and vigilant. An idle person will also portrays realistically the slums of Karachi in a few appreciates the working woman who has practically turned her work into an woman walks softly with the delicacy and rhythm of a dancer's feet.

. Paraphrase:


A Sindhi woman is going through a bazaar with bare feet. She was body and floating dress. The wind pushes the cloth impressively and there is a rhythm in her movement which can be seen in swaying carrying stone jar on her head. She walks as smoothly as the wave of a stream. passing scene of a Karachi slum. The poet meditates and sees his own body that is bent by her from her face. She is She is through stones, garbage, pieces of bread and the broken glass. This is the time. He observes that only those who bear the burden of life and carry its hardships through life are strong and straight. Glossary wave like motion or look move along smoothly walk undulant glide tread garbage waste, worthless or rubbish excrement waste matter expelled from the body.

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First Year at Harrow

Description:
I had scarcely passed my twelfth birthday when I entered the inhospitable regions of examinations, through which for the next seven years I was destined to journey. These examinations were a great trial to me. The subjects which were dearest to the examiners were almost invariably those I fancied least. I would have liked to have been examined in history, poetry and writing essays. The examiners, on the other hand, were partial to Latin and mathematics. And their will prevailed. Moreover, the questions which they asked on both these subjects were almost invariably those to which I was unable to suggest a satisfactory answer. I should have liked to be asked to say what I knew. They always tried to ask what I did not know. When I would have willingly displayed my knowledge, they sought to expose my ignorance. This sort of treatment had only one result; I did not do well in examination.

/>
This was especially true of my Entrance Examination to Harrow. The headmaster, Mr. well don, however, took a broadminded view of my Latin prose: he showed discernment in judging my general ability. This was the more remarkable, because I was found unable to answer a single question in the Latin paper. I wrote my name at the top of the page. I wrote down the number of the question T. After much

reflection I put a bracket round it thus (D). But thereafter I could not think of anything connected with it that was either relevant or true. Incidentally there from nowhere in particular a blot and several smudges. I gazed for two whole hours at this sad spectacle: and then merciful ushers collected my piece the others and carried it up o the Headmaster's table. It was from these slender indications of scholarship that Mr. well don drew the conclusion that I was worthy to pass into Harrow. It is very much to his credit. It showed that he was a man capable of looking beneath the surface of things: a man not dependent upon paper manifestations. I have always had the greatest regard for him. of foolscap with all In consequence of his decision, I was in due course placed in the third, or lowest, division of the Fourth, or bottom. The names of the new boys were printed in the School List in alphabetical order and as my correct name, Spencer-Churchill, began with an 'S', I gained no more advantage from the alphabet than from the wider sphere of letters. I was in fact only two from the bottom of the whole school; and these two, I regret to say, disappeared almost immediately through illness or some other cause.

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Different components of a network

DESCRIPTION:

Different component of a network are.....

1).Communication Media:

Communication media is used to transfer data from one computer to another computer Low cost LAN  are connected with twisted wire pair Many LAN use coaxial or fiber-optic cables These cables are expensive but provide faster communication Some LAN use wireless transmission media. It uses infrared or radio waves to connect computers Wireless networks are easy to setup and maintain. However, they have low transmission  rates and limited distance between two communication devices.

2).N I C:

N I C stands for Network Interface Card (N I C) It is also known as LAN adapter t is used to connect a computer to a network It is a circuit board installed on the motherboard. other board. Each Nowadays, most computer systems have a network card built into the m computer on the network must have a network card Different types  network cards are available Wireless network cards have an antenna that sends and receives data.

3).Bridge:

Bridge can be used in computer networks to interconnect two LAN When a bridge receives a signal, it determines the segment where the signal shown 3. Bridge separate network segments. A segment is a section of a network sent. It reads the addresses of sending and receiving computers. The bridge does not signal to the other segment if sending and receiving computers are both in the same It reduces network traffic and increases network performance.

 

4).Router:

Router work multiple networks using communication A router is a communication device that connects different protocols. It manages the best route between any two co Routers are used when several networks are connected together. A router network of any size. It can connect networks of different countries. They transfer time. The router is an intelligent device. It uses algorithms to find out the best path data to a network.

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NUCLEAR REACTOR

Description:

It is a device in which nuclear fission chain reaction takes place at a constant rate in a controlled manner. It is  used to produce nuclear energy for industrial and other useful purposes.
principle:
Controlled Fission chain Reaction is the principle of a nuclear reactor.

Explanation:

 The role of reactor in a nuclear power station is the same as that of a furnace in a thermal power station.  Heat energy  is produced in Fission reaction. This energy is used to rotate a turbine. The turbine rotates the generator which produce electricity. The sketch of a nuclear power station is shown in figure.

construction:

The main part of a nuclear reaction types. Here fuel is kept in the form of cylindrical tubes Reactor fuels are type uranium  was used as fuel in the elementary reactors. In this fuel the quantity of  is only 0.7 % in naturally occurring uranium 2. Moderator: 135 235 of U is increased fr 92 the fuel rods are placed in a substance of small atomic weight, such as water, heavy water, carbon o absorbed carbon etc, these substances are called moderators.
Function:

 The function of these moderators is to slow down the speed of neutrons produced during fission process. Heavy water Hydrogen instead of H. The neutrons produced in the fission reaction are very fast and are not suitable for is made of H, a heavy isotopes further fission in u and Pu. For this purpose stow neutrons are more useful. To slow down the fast neutrons into slow neutrons moderators are used. 235 239 action. only from each 92 or  94.

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RADIOACTIVITY

                                 

Description:

The elements having charge number z greater than 82 are unstable. They emit invisible radiation which effect the photographic plate. Such element  are called radioactive elements and the process is called Radioactivity. The radiations emitted by radioactive elements are of three types named as alpha Beta and g. Radioactivity is a purely nuclear phenomenon. It is not affected by physical or chemical reaction. Radioactivity does not depend upon physical state of the radioactive material such as temperature, pressure, density etc.


Discovery:
Radioactivity was discovered by Henri Becquerel in 1896. He found that an ore containing uranium {z = 92} emits an invisible  radiation which penetrates through a black paper wrapping a photographic plate and effects the plate.
Conclusion:
From this experiment we conclude that: 1) All radiations from radioactive material are not alike (same). (2) The radiations bending towards the negative plate are positively charged particles; called a-particles (3) The radiations bending towards the positive plate are negatively charged particles, called p-particles (4) The radiations that go straight without bending have no charge on them. These are called g-rays

a-Particles:
They are helium nuclei. Each a-particle has 2-protons and 2-neutrons charge number
2 2 mass number A 4

B-Particles:

They are fast moving electrons (i.e.) coming out of nucleus.  charge number Z-1 mass number then from A o
 Y-Rays:
Like x-rays, y-rays are electromagnetic rays coming out of nucleus. The wavelength

of y-rays is mu than the X-rays. They have very high frequency.

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