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When you watch it properly




Most modern methods of telecommunication employ electricity. In 1820 scientists discovered that an electric current could deflect a magnetic needle to the left or to the right. It depends on the direction in which the current flows. This discovery allowed the invention of the telegraph.

The telephone, which transmits speech, was a later invention. The vibrations of a voice speaking into a microphone of a telephone cause vibrations in an electric current. This current travels along a wire to a receiver. In this receiver there is a thin metal plate and it repeats the vibrations of the original voice.

Television can transmit moving pictures. People often ask about harmful emission that the TV-set generates. Specialists reply that the TV-set does not create any harmful electromagnetic field because it is not an emitting apparatus; it is a device that converts emission into a visible image. Its electromagnetic field does not differ from the electrical wirings field in the room. It is true that the TV-sets kinescope is elecrostatically charged, but its intensity drops practically to zero at a half-a meter distance from the screen. And hardly anyone watches the TV so close. Watch TV from the distance not less than three metres, specialists recommend.

Some people leave the lights on when they see a TV program and others switch them off. Who is right? Specialists recommend watching TV with the light on, but there is no need to use many lamps.

The problem of how long a person may stay in front of the TV-set is also important. You should have a break after you watch a program for an hour and a half. Just change your position, stretch your legs and relax.

.

1. to deflect magnetic needle a. ,
2. to leave the lights on b.
3. to cause vibrations in electric current c.
4. electrical wirings field d.
5. to convert emission into an image e.
6. to transmit a picture f.
7. there is no need g.
8. to drop to zero h.

, , (1-5) (a-e).

1) The magnetic needle deflects in the direction .

2) A thin metal plate in the receiver .

3) The electromagnetic field of a TV-set does not differ

4) The TV-sets kinescope is

5) When you watch TV with the lights on,

a). from the electrical wirings field in the room.

b). repeats vibrations of a voice.

c). ....there is no need to use many lamps.

d). ... in which the electric current flows.

e). ... electrostatically charged.

, . T (True), , F (False), .

  Statement True False
1. In 1820 the scientists discovered a telegraph.    
2. In a telephone there is a microphone.    
3. Television transmits visible images.    
4. People get ill when they watch TV leaving the lights on.    
5. The problem is how a person can eat in front of a TV-set.    

, .

1. What does modern telecommunication employ?

2. What is a TV-set?

3. Why is a TV-set harmless?

4. Why do specialists recommend watching TV from the distance?

5. What should you do after you watched TV for a long time?

.

, , . .

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III

I. .

1. It . dark at 8 oclock in the evening.
    ) are b) is ) am  
2. My parents . at home now. My father is at work, my mother is in the shop.
    ) is b) are ) arent  
3. Your English . good. Try to do more exercises.
    ) are b) is not ) is  
4. I . very tired. I must go to bed.
    ) am b) am not ) are  
5. My friends students of Tomsk Polytechnic University.
    a) is b) are c) isnt  
6. Probably we out next morning.
    a) were b) was c) will be  
7. The hotel was very comfortable and it . expensive.
    a) was b) was not c) were  
8. The old bread . on the table in the garden. The birds ate it.
    a) will be b) were c) was  
9. Do you think the examination .. difficult?
    a) will be b) will not c) were  
10. ..the weather good when you were on holiday?
    a) were b) was c) were not  

II. to have .

1. My parents . (have) many relatives.

2. This cat . (have) very sharp claws.

3. The student is not very attentive. He . (have) many mistakes.

4. This town . (have) many famous monuments.

5. Sarah . (have) a new job.





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