(a) Draw a labelled diagram to show the domestic electric wiring from an electric pole to a room. Give the wiring for a bulb and a three-pin socket only.
(b) State two hazards associated with the use of electricity.
(c) State the important precaution which should be observed in the use of electricity.
(d) What will you do if you see a person coming in contact with a live wire?
(e) Explain why, electric switches should not be operated with wet hands.
(a)
(b) The two hazards associated with the use of electricity are as follow:
1. Due to damaged wiring or overloading, a short circuit may occur which can cause an electrical fire in a building.
2. There is a high chance of getting an electric shock, if a person touches a live electric wire.
(c) The important precaution which should be observed in the use of electricity are:
1. A proper earth connection should be given to electrical appliances, to avoid the risk of electric shock.
2. Wires used in domestic wiring must be of good quality, with the proper thickness, and of insulation.
3. All the switches, fuses and circuit breakers should be connected in series with the live wire.
4. Electrical appliances should not be touched with wet hands.
(d) If a person comes in contact with a live wire, we will immediately turn off the main switch at once, to cut off the electricity supply.
(e) Electric switches should not be operated with wet hands because water is a good conductor of electricity. Thus, touching the switches with wet hands we ma get an electric shock.
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