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Дидактичнi розробки для студентiв 4 курсу РТФ.doc
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VI. Complete the following sentences, using active vocabulary:

1. Filaments and indirectly heated cathodes of oxide-coated type consist of ….2. Vacuum tubes are made in all sizes from … 3. Many of the basic principles of radio were well understood for….4. Metallic conductors are composed of …5. If the temperature of a conductor is raised sufficiently, some of free electrons …6. The operating temperature is close to the melting point of …7. Emitters made of tungsten are used principally in large … 8. Almost of tubes of the small receiving type, as well as many…

VII. Which of the following statements are true or false? If the statement is wrong, correct it:

1. Of all the component parts used in modern systems radio communication, the electron tube is the most important one. 2. Tungsten emitters must be operated at 273° (degrees Kelvin = degrees Centigrade +2.500°). 3. This type of cathode has, therefore small emission efficiency. 4. Vacuum tubes are made only one size. 5. Metallic conductors are composed of atoms and electrons.

VIII. Answer the following questions:

1. What is the most important of all the components in modern systems of radio communication? 2. In what sizes are vacuum tubes made? 3. What are metallic conductors composed of? 4. What process is known as thermionic emission? 5. Where are emitters made of tungsten used? 6. At what temperature must tungsten emitters be operated? 7. What is thoriated tungsten? 8. When does migration of thorium atoms produce are activated layer on the filament surface? 9. What do filaments and indirectly heated cathodes consist of?

IX. Put the questions to the following sentences:

1. Many of the basic principles of radio were well understood for years before. 2. Thoriated tungsten is tungsten containing a small percentage of thorium oxide. 3. Tungsten emitters require relatively large amounts of power for heating. 4. The operating temperature is close to the melting point of tungsten. 5. Construction an electron microscope became possible after numerous experiments. 6. An electric conductor being moved in a magnetic field, an electric current is generated.

X. Translate the sentences. Define the function of Gerund:

1. He likes reading English scientific books. 2. They think of applying electronic devices in their laboratory. 3. This little girl likes being read to. 4. Flying into outer space has been man’s age old dream. 5. Our government takes great care of the development of science b providing our scientist with all necessary things for their research work. 6. Before carrying out this experiment he carefully examined all the instruments. 7. Many Institutes have been established for training specialists for various branches of our national economy. 8. The idea of building artificial satellites belongs to K.Tsiolkovsky. 9. After producing the electronic equipment we raised the efficiency of some processes. 10. In our country great progress has been achieved in developing all branches of science and engineering. 11. Soviet scientists having made the great contribution to the cause of conquering cosmic space as well known in the whole world. 12. We where told about their having studied a number of problems connected with the development of radio electronics. 13. Their wish is mastering the fundamentals of radio engineering. 14. Scientists could not improve without making numerous investigations in this branch of radio engineering. 15. Look at the readings of the meter.16. The thorough mastering of English is extremely necessary for engineers.