2. Define what conjunction could be inserted in the following joined clauses:

1. The Curies found polonium was many times more active than uranium. 2. In 1898 they announced they had discovered the element radium. 3. They claimed radium radiations were a then hundred thousand times more active than pitchblende from which it was obtained. 4. It is established there are there varieties of radiations from radioactive atoms. 5. The discovery of the radiations radioactive substances emit was of the greatest importance for research work in the field of the structure of the atom. 6. The application the radioactive isotopes are finding in different fields of life is of growing importance. 7. The properties of a composite matter are always quite different from those of the elements it consists of. 8. We can now calculate how many atoms there are in 1gramme of any element we choose by making use of our knowledge of the relations between the atomic weights of the elements.

3. Translate the following dialogue into English:

- Какой новый мощный источник энергии был открыт учёными в начале ХХ столетия?

- Этот новый источник энергии – атомное ядро.

- Долго ли работали учёные над раскрытием тайны атома?

- Да, они работали больше столетия.

- Как иногда называют наш век?

- Его называют атомным веком.

- В чём преимущество атомной энергии?

- Атомная энергия очень дешёвая и её запасы неограниченны.

- А знаете ли вы, что такое изотопы?

- Конечно. Это элементы с такими же химическими свойствами, как и у естественных элементов, но они обладают свойством радиации. Применение изотопов также является примером мирного использования атомной энергии в нашем народном хозяйстве.

4. Answer the following questions:

1. What are the achievements of science in nuclear physics?

2. By what process is the splitting of the atomic nucleus accompanied?

3. For what purposes can atomic energy be used?

4. For what purposes is the atomic energy used in the Soviet Union?

5. What improvements in the life of man can the peaceful use of atomic energy bring?

6. How many days will it require to go around the sun in an airplane?

7. What is the diameter of the sun?

8. What is the internal temperature of the sun?

СРС 4

Read the text: History of electronics

Electronics is the science dealing with devices operated by control of the movement of electric charges i a vacuum, in gases, or semiconductors; or with the processing of information or the control of energy by such devices. This definition covers the whole complex family of vacuum and gaseous electron tubes and their applications. It also includes metallic contact or semiconductor rectifiers and the transistors which utilize the control of electrons or positive charges (holes) to process information or to convert energy.

Electronics was born in the 19^th century. Like hydrolysis or chemistry it has come into is own only recently. Electronics first established itself, however, in wireless telegraphy. Industrial applications of electronics include control gauging, counting, heating, speed regulation, ets.

But in a larger field, electronics leads to automatic control of large-scale industrial operations.

Today, electronics has started a new era. Electronic devices are doing simple, but human-like thinking. Some industries are controlled , by electronic robots. Automation is the industrial keynote of the day. Planes and rockets are electronically controlled. Some radiotelescopes work like radar to receive radio waves from outer space. Shortly speaking, electronics is not so much a new way of looking at electricity.