Question

Earthing wire in domestic electric circuits is a safety measure. Justify this statement explaining its role in case of accidental leakage of electric appliances.

Metallic electrical appliances are connected to the mains through a three pin plug, whereas electrical bulb with two pin plug.

In our homes, we receive supply of electric power through a main supply (also called mains), This supply, usually with red insulation cover, is called live wire (or positive). Another wire, with black insulation, is called neutral wire (or negative). In our country, the potential difference between the two is 220 V. At the metre-board in the house, these wires pass into an electricity meter through a main fuse. Through the main switch they are connected to the line wires in the house. These wires supply electricity to separate circuits within the house. Often, two separate circuits are used, one of 15 A current rating and other of 5 A current rating.. The earth wire, which has insulation of green colour, is usually connected to a metal plate deep in the earth near the house.