Work in pairs. Draw a circuit of a triode and ask your partner some questions based on it. Make sure all the questions and answers are in Present Continuous.

Date: 2015-10-07; view: 414.

Speaking

Table B

Table A

Match the terms in Table A with their definitions in Table B

1. cathode

2. triode

3. amplification

4. electrode

5. plate

a. A vacuum tube having three electrodes or a semiconductor rectifier having three connections.

b. The negatively charged electrode by which electrons enter an electrical device. The opposite of anode.

c. The positively charged electrode by which the electrons leave a device. The opposite of cathode.

d. An increase in strength or intensity, especially of sound.

e. A conductor through which electricity enters or leaves an object, substance, or region.

For example:

Student A - In what direction are the electrons shown in the scheme moving?

Student B – They are moving towards the plate.

17. Summarize the text “Triodes” in 150 words using the following plan:

1. The structure ofa vacuum-tube triode.

2. The principles of its work.

3. The function of a grid.

4. The influence of the distance between the cathode and the grid on the electron flow.

5. The influence of the voltage on the current flow.

6. The grid application.

18. Compare a vacuum-tube triode with a diode using appropriate degrees of comparison and the following words of comparison and contrast: both, like, whereas, unlike, but, however.