XII. State whether the following statements are true or false. Use only evidence from text.

Date: 2015-10-07; view: 352.

a. Vacuum tubes are smaller than transistors and consume less power.

b. The emitter usually has a negative electric charge and the collector usually has a positive charge.

c. Electric current outside the tube flows through the collector and heats it.

d. The grid consists of a wire mesh located between the emitter and the collector.

c. The current of electrons flows from the emitter to the collector.

XIII. Match the words and word-combinations from text 15A with their corresponding definitions:

1. vacuum tube a. an electron tube evacuated to a sufficiently low pressure that its electrical characteristics are independent of any residual gas

2. integrated circuit b. a two-electrode tube

3. transistor c. vacuum tubes filled with low-pressure gas

4. diode d. a semiconductor device with at least three terminals, used in circuit as an amplifier, detector, or switch

5. electrode e. a solid electric conductor through which an electric current enters or leaves an electrolytic cell or other medium

XIV. Translate the following two-component and multi-component terms into Ukrainian:

multielectrode tube, cathode-ray tube, microwave tube, gas-filled tube, semiconductor triode, hard tube, soft tube, thermal emission, discrete device, integrated circuit.