Exercises

I. Learn the following words, groups of words. Translate the sentences.

1. air — воздух. Air is a poor conductor of electricity.

2. bare wire — оголенный провод. A bare wire is a wire not covered with insulating material.

3. cord — шнур. A cord is a small insulated cable.

4. to cover — покрывать. The train covers a great dis­tance from Moscow to Vladivostok.

5. electrical engineering — электротехника. We study electrical engineering.

6. glass — стекло; стакан. Glass is a good insulator. We need glasses for a chemical experiment.

7. insulation — изоляция. If a wire is covered with in­sulation it is called an insulated wire.

8. to leak off — утекать. If there is no insulation the current can leak off the conductor.

9. opposition — противодействие, сопротивление. When the temperature rises opposition to the passing current increases.

10. pole — полюс; столб, опора. Any magnet has two poles. What are the poles of a transmission line made of?

11. to resist — сопротивляться, противодействовать. We shall consider the ability of insulators to resist the current flow.

12. rubber — резина. Rubber is a perfect insulator.

13. similar — одинаковый, похожий, однородный. Some liquids have similar properties.

14. socket — розетка, патрон (электролампы). Copper wires connect electrical devices to the socket.

15. to turn off — выключать. If the switch is turned off' the current does not flow.

16. to transmit — передавать (электроэнергию); посы­лать. Electricity is transmitted by wires.

II. Translate the following groups of words.

air insulator, similar conditions, to cover, the wires, electrical engineering, wall socket, North pole

выключать свет, стеклянные изоляторы, оголенный провод, передавать электрический ток, покрытый ре­зиной, высокий столб

III. Complete sentences according to the model given below.

Model: The method used ... . → The method used is described in the present article. Исполь­зуемый метод описан в данной статье.

1. The device tested ... . 2. The results obtained ... . 3. The temperature measured ... . 4. The phenomenon studied ... . 5. The conductors used ... . 6. The substance mentioned ... . 7. The method proposed ... .

IV. Translate the following groups of words.

research work—research work plan; water pipe—water pipe material—water pipe material quality; power supply— power supply increase—power supply increase problem; transmission line—transmission line wire—transmission line wire insulation; space investigation—space investiga­tion program—space investigation program discussion

V. For the words given in (a) find the Russian equivalents in (b).

a) 1. wire; 2. statement; 3. to cause; 4. collision; 5. to control; 6. feature; 7. similar; 8. direction; 9. opposition; 10. positive; 11. path; 12. to consider; 13. as well; 14. to expect; 15. to place

b) 1. положительный; 2. также, тоже; 3. считать, рас­сматривать; 4. направление; 5. ожидать, рассчитывать; 6. помещать; 7. путь, контур; 8. противодействие; 9. особенность; 10. подобный; 11. столкновение; 12. уп­равлять; 13. утверждение; 14. вызывать, заставлять; 15. проволока

VI. Answer the following questions.

1. What is discussed in the present article? 2. Do all substances conduct the electric current easily? 3. What is a conductor? 4. What does conductance depend upon? 5. What materials are the best conductors of electricity? 6. Does temperature influence the conductor’s resistance? 7. What is the difference between a conductor and an insu­lator? 8. What insulators do you know? 9. Why are power transmission line wires bare? 10. What insulation is used on the cords of your electrical devices? 11. Can we do with­out insulators?

VII. Explain why:

1. we need conductors and insulators. 2. we compare water flow and current flow. 3. we mostly use copper conductors. 4. the current flows when you turn on the light. 5. lightning strikes the nearest conductor. 6. there must be a difference of potential in the circuit.

VIII. Make up the annotation of the text and retell it.