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UNIT 8

I. Выпишите из Прил. 1 значения следующих слов, запомниве их:

straight (a), hole (n), glow (n), narrow (a), similar (a), enormous (a), widen (v), coat (v), strike (struck, stricken) (v), spot (n), screen (n), amount (n), set (n), pair (n), point (n).

II. Выпишите из Прил. 2 значения следующих терминов, запомните их:

cathode ray tube

electron gun

deflector plate

III. Прочтите следующие интернациональные слова и дайте их русский эквивалент:

electrode (n), gas (n), line (n), modern (a), opposite (a), lens (n), vertical (a), horizontal a), chemicals (n).

IV. Образуйте существительные от следующих глаголов, используя суффиксы: -ment, -ion (-tion), -у, -ity, -age, -er (-or)

develop, discover, deflect, heat, pass, act, attract, apply, move, produce, similar.

V. Прочтите текст, замените местоименными повторами подчеркнутые слова. Раскройте логико-смысловую функцию слов-гидов. Переведите текст.

The cathode ray tube (crt) is used in oscilloscopes, radar receivers and television sets. By means of a crt, an oscilloscope not only shows the size of a signal, but also how the signal varies with time. In other words an oscilloscope shows the waveform of the signal.

The crt operates as follows. First electrons are emitted from a heated cathode. Then these electrons are accelerated to give them some velocity (скорость). Next these electrons are formed into a beam which can be deflected vertically and horizontally. Finally these electrons are made to strike a screen coated on screen's inner surface with a phosphor.

VI. Прочтите текст, разделите его на логико-смысловые единства, озаглавьте их.

CATHODE RAYS AMD CATHODE RAY TUBE

1. When a voltage is applied between two electrodes sealed into a tube from which most of the gas has been removed, a stream of electrons passes from the negative electrode (cathode) to the positive electrode (anode). Because the stream travels in straight lines, like light rays, they are called cathode rays. If the anode has a hole in it, the cathode rays will pass through it and strike the end of the glass tube producing a greenish glow. It was from the study of cathode rays that J. J. Thomson discovered electrons in 1897. This discovery led to the development of the whole field of electronics.

2. The modern cathode ray tube uses a narrow beam of electrons produced by heating the filament similar to the one in a thermionic valve. The beam is focused by a system of cylindrical electrodes, which act in the same way as a lens acts on a beam of light. The system of electrodes together with the filament is called an electron gun. The electrons travel at the enormous speed of about 80 000 km per second. The widened end of the tube opposite the electron gun is coated with chemicals (phosphor) which glow when struck by the electron beam and produce a green spot on the screen.

3. As electrons are negatively charged they are attracted by a positive charge and repelled by a negative charge. Inside the tube there are two sets of deflector plates. One set is vertical and the other horizontal. When voltages are applied to the deflector plates the electron beam, and thus the spot of light on the screen, can be moved up and down from side to side. The amount of deflection is in proportion to the voltage applied to the plates. By applying voltages to both pairs of plates at the same time the spot can be moved to any point on the screen.

(1,700)

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