Exercises

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

1. alternating current — переменный ток. The alternat­ing current is used in our homes and factories.

2. as well— также. M.V. Lomonosov knew German, French, Greek and Latin as well.

3. to be certain — обязательно, несомненно. The lec­ture is certain to begin in time.

4. to consider — рассматривать; считать. We must con­sider this question as soon as possible. We consider your answer to be wrong.

5. to decrease — уменьшить, понижать. Atmospheric pressure decreases before thunderstorm.

6. to determine — определять. The students will deter­mine the steam pressure in the turbine.

7. direction — направление. We must determine the di­rection of the wind.

8. direct current — постоянный ток. A battery is a source of a direct current.

9. to increase — возрастать; увеличивать. The energy needs of the world are increasing.

10. to meet requirements — удовлетворять требованиям. These instruments meet modern requirements.

11. particle — частица. What particles does the atom consist of?

12. to require — требовать. This test requires much time.

13. statement — утверждение; формулировка. Lomonosov's statements are quite correct.

14. subject — предмет; тема. We study different subjects. What is the subject of your report?

15. terminal — зажим, вывод, клемма. There are two ter­minals in the battery.

16. voltage — напряжение. High voltage is dangerous.

17. wire — проволока, провод. Wires are made of differ­ent metals.

II. Learn to recognize the following international words.

static, electrolyte, cycle, theory, result, thermometer, boiler, contact, fact

III. Translate the following groups of words.

to increase voltage, negative terminal, opposite di­rection, electrical wires, charged particles, to meet indus­trial requirements, important statement

интересный предмет, важное заявление, уменьшить тепло, зажим батареи, стальная проволока

IV. Answer the following questions.

1. Who first produced a source of continuous current? 2. After whom was the unit of current named? 3. Who de­termined the difference between the current and the stat­ic charges? 4. What did Ampere suppose? 5. What can you say about an electron? 6. What charges do you know? 7. When does a wire carry an electric current? 8. Do liquids conduct current? 9. What can you say about the electrolytes? 10. What do you call d.c.? 11. What is the advantage of a.c.? 12. Where is a.с. used? 13. Who first applied a.c.?

V. Ask your group-mate the following questions. Let him/her answer them.

1. if electricity is a form of energy. 2. if there are two types of electricity. 3. if alternating voltage can be in­creased and decreased. 4. if Franklin made an important contribution to the science of electricity. 5. if Ampere determined the difference between the current and the static charges. 6. if the electric current can flow through liquids and through gases. 7. if the electrolytes change greatly when the current passes through them. 8. if a negatively charged electron will move to the positive end of the wire.

VI. Put two questions to each paragraph of the text. Ask your group-mates to answer them.

VII. Find the wrong statements and correct them.

1. Electrons flow from the positively charged terminal of the battery to the negatively charged terminal. 2. Ampere supposed the current to flow from the negative pole to the positive one. 3. Static electricity is used for practical purposes. 4. Static electricity is not very high in voltage and it is easy to control it. 5. To show that the charges are unlike and opposite Franklin decided to call the charge on the rubber positive and that on the glass negative. 6. Galvani thought that electricity was generated because of the contact of the two dissimilar metals used. 7. Volta took great interest in atmospheric electricity and began to carry on experiments. 8. The direct current is known to flow first in one direction and then in the opposite one. 9. The direct current used for power and lighting purposes is assumed to go through 50 cycles a second.

VIII. Explain why:

1. Static electricity cannot be used to light lamps, to boil water, to run electric trains and so on. 2. Voltage is increased and decreased. 3. The unit of electric pressure is called the volt. 4. Students must learn English. 5. Ampere was wrong as to the current direction. 6. The current is said to flow from the positive end of the wire to its negative end.

IX. Define the following terms.

battery, alternating current, direct current, static electricity, electric current, wire, laboratory, terminal, electron

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