Ex.1. Match the words (1-6) with the definitions (A-F).

4. voltage 4. ohm

5. AC 5. current

6. DC 6. volt

A. a measurement of the force of electricity;

B. a current that flows in two directions;

C. a measurement showing resistance;

D. the quantity of electricity in a wire;

E. the strength of moving electricity;

F. a current that flows in one direction.

Ex.2. Fill in the gaps with the words from the box.

1. A(n) ……. is too small to see without a powerful microscope.

2. Many wires are made out of copper because of its low …. .

3. A(n) …….. measures how much electrical power is being used.

4. A common way to measure electric current is …. .

Ex.3. Listen to the dialogue and mark the statements as true (T) or false (F).

1. The student doesn’t understand the difference between two types of currents.

2. Remembering what the letters stand for helps the student.

3. The student is learning about AC and DC for the first time.

Ex.4. Listen again and complete the conversation.

Instructor: Yesterday, we discussed AC and DC. Now, let’s move on to…

Student: Excuse me, Mr. Green. I still don’t understand ……………………..

Can you explain that again?

Instructor: Sure, do you remember…………………………………………….?

Student: Yes, AC is……………… DC is ………………….

Instructor: Good! Now, simply remember this:……………………………….

Student: What do you mean?

Instructor: Alternating current ………………….. It goes back and forth. ……

………. does not.

Student: Oh, ………………… Thanks.