nd a number of lighter negatively charged particles called electrons, which revolve around the nucleus. Normally each atom of a substance is electrically neutral, or it has equal amounts of negative and positive charges, i. e. produces no electrical current. When an electric charge is at rest it is spoken of as static electricity, but when it is in motion it is refeared to as an electric current.
An electric current which flows in the same direction through a conductor or a current which does not change its polarity is called a direct current or a continuous current. An alternating current flows first in one direction and then in the other.
Task 2. Match the questions with the answers. (Соотнесите вопросы с ответами. )
1. Whatiselectricity?
2. What are the sources of electricity?
3. What properties ofelectricity have made it widely used?
4. What are the advantages of electricity?
5. What are home uses of electricity?
a) Lighting, heating, various time and labour saving appliances, radio, television, video and others.
b) It is a source of electric power used in everyday life and industry.
c) Electrostatics and electromagnetism.
d) Clearness, easy regulation, no by-products, low cost, improved service.
e) Batteries, generators, electric motors and other devices.
Task 3. Complete the sentences using the suitable words given below, guess the title of the text. ( Дополните предложения, подставивслова, данные ниже, отгадайтеназваниетекста. )
is generated by converting heat, light, chemical energy, or mechanical energy to electrical energy.
Most electrical energy is produced in large by conversion of mechanical energy or heat.
- generated by the conversion of light or chemical energy is use
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