5. Domestic circuits

1. In which case does a short circuit happen in an electrical system? 

 

Closed wireClosed circuitOpen CircuitOverloading can happen when the live wire and the neutral wire not in contactcome into direct contactremains samenot in the direct contact. (This happens when the insulation of wires is damaged or there is a defect in the appliance.) In these situations, the current in the circuit suddenly unequaldeflectingdecreasesincreases. This is called short-circuiting.

 

2. What role does the earth wire play in an electrical circuit? Why is it important to connect metallic appliances to the earth?

 

The earth wire, which has black colourgreen colouryellow colourred colour insulation, is generally attached to a metal plate deep in the earth near the house. This is used as a safety measure, particularly for appliances with a metallic body.

 

The metallic body is attachedis not attachednot fixednot adhered to the earth wire, which provides a low-resistancehigh reactancehigh-resistancehigh impedance conducting path for the current. Thus, it assures that any leakage of current to the metallic body of the appliance keeps its potential to that of the earth, and the user may not get a severe electric shockno shockchance of electric shockmay get a severe electric shock.