to compose — составлять, состоять

atom — атом

to be made up of — состоять

nucleus- ядро

to revolve- вращаться

tremendous – огромный

they overlap to some extent- они взаимно проникают в какой то мере

to apply – применять

circuit – схема, цепь

rate [reɪt] — норма, скорость

Exercise 1.1. Answer the questions:

1. What is the constitution of matter?

2. What is an atom?

3. What charges are called electrons?

4. What does the nucleus consist of?

5. Have neutrons any charges?

6. When is the atom neutral?

7. What is a negatively charged body?

8. What is a positively charged body?

9. What is an electric current?

10. Has the conductor equal numbers of positive and negative charges in its atoms?

11. Why are metals dense?

12. When can the outer electrons pass from one atom to another?

Exercise 1.2. Find the following words and word combinations in the text:

1. строение материи

2. материя состоит из атомов

3. вращаются вокруг ядра

4. на огромной скорости

5. один положительный заряд

6. содержит равное количество

7. отрицательно (положительно) заряженное тело

8. источники разного напряжения

9. расположены очень близко

10. разница в напряжении

11. сила тока

12. зависит от скорости движения

электронов

Exercise 1.3. Translate into English:

1.Атом состоит из положительно заряженного ядра, окружённого отрицательными зарядами.

2. Электроны вращаются вокруг ядра на огромной скорости.

3. Ядро состоит из протонов и одного и более нейронов.

4. У протонов один положительный заряд, а у нейтронов заряда нет.

5. Внешним электронам сравнительно легко перемещаться из одного атома в другой.

6. Проводник содержит равное количество положительных и отрицательных зарядов.

7. Батарея вызывает разницу в напряжении между концами проволоки.

8. Электрический ток — движение электрона в сторону положительно заряженного электрода.

9. Сила тока зависит от скорости движения электронов через проводник.

Exercise 1.5. Translate the text

Вариант 3

Read the text:

WHAT IS AN ELECTRON?

1. What is an electron? We can think of the electron as a very small, indivisible, fundamental particle — a major constituent of all matter. All electrons appear to be identical and to have properties that do not change with time. Two essential characteristics of the electron are its mass and its charge. Qualitatively, we can think of an electron as a "piece of matter" that has weight and is affected by gravity. Just as the mass of any object is defined, we can define the mass of the electron by applying a force and measuring the resulting rate of change in the velocity of the electron, that is, the rapidity with which its velocity changes.

2. This rate of change is called acceleration, and the electron mass is then defined as the ratio of the applied force to the resulting acceleration. The mass of the electron is found to be about 9.11х10-28 grams.1 Not only the electron but all matter appears to have positive mass, which is equivalent to saying that a force applied to any object results in an acceleration2 in the same direction as the force. How does the other aspect, the charge of the electron, arise? If we investigate further, we find that all electrons have an electric charge, and the amount of charge, like the mass, is identical for all electrons. No one has ever succeeded in isolating an amount of charge smaller than that of the electron. The sign of the electron charge is conventionally defined as negative; the electron thus represents the fundamental unit of a negative charge.

3. No experiment has yet succeeded in removing the charge from the electron, leaving only its mass. Therefore, instead of considering the electron a "massive" body that has somehow acquired a charge, it seems more realistic to think that the charge and the mass are two inseparable aspects of a single unity. The motion of an electron, like that of any other body, results from a force acting on it. How can force be applied to an electron? One way is by gravity. Another is by bringing a second charge near the electron, thus exerting an attractive or repulsive force on it. In this case we may say that the second charge sets up electric field which applies a force to the first charge. Finally, we find that an electric current flow will affect the motion of a nearby charge, but only if that charge is already in motion. In this case, we say that the current sets up a magnetic field which applies a force to the moving charge. These three are the only known ways of applying force to an electron. The relationship between these fields, the charges producing them and resulting effects on other charges are the laws of electron motion.