8. Here are some circuit symbols. Label them and describe their function.

e.g. It’s called a transformer. It steps AC voltages up and down.

		1. fixed resistor 2. voltmeter 3. variable resistor 4. variable capacitor 5. transformer 6. fuse 7. switch 8. milliammeter 9. diode 10. aerial (antenna)
a) varies capacitance in a circuit b) rectifies alternating current c) adds resistance to a circuit d) measures very small current e) breaks a circuit	f) protects a circuit g) varies the current in a circuit h) steps AC voltage up or down i) receives RF signals j) measures voltages

9. Study the block diagram of a battery charger. Match each component or unit with its function in a battery charger.

Component / Unit	Function
1. transformer 2. rectifier 3. smoothing circuit 4. stabilizing circuit	a) steps down the AC mains voltage b) prevents the output from changing when the load varies c) removes the fluctuations in the DC output of the rectifier d) converts the AC voltage to a DC voltage

Writing.

10. Write the description of the battery charger and the function of each building block. Your description should answer these questions.

1. What is the function of a battery charger?

2. What does it consist of in terms of blocks?

3. How are the blocks connected?

4. What is the function of each block?

11. Write the translation of the paragraph which your teacher will give you into Russian.

lesson 4. personal Computer

Lead-in.

1. Answer these questions.

1. Do you have a computer?

2. How often do you use your computer?

3. What do you need your computer for?

4. Look at the picture above. Say the names of a computer parts you see. What other ones do you know?

5. How do you care about your computer?

2. Do you know what these terms mean? Match each item in Column A with its function in Column B.

1. RAM 2. processor 3. mouse 4. clock 5. flash memory key 6. monitor 7. keyboard 8. DVD-ROM drive 9. cache 10. ROM

a) controls the cursor b) inputs data through keys like a typewriter c) displays the output from a computer on a screen d) reads DVD-ROMs e) reads and writes to electronic chips on a card f) holds instructions which are needed to start up the computer g) holds data read or written to it by the processor h) provides extremely fast access for sections of a program and its data i) controls the timing of signals in the computer j) controls all the operations in a computer

Reading and Vocabulary.