Question

b) Give reasons for the following:
1. Household electric wires are covered with plastic or rubber.
ii. An electrician only replaces a blown off fuse with a wire prepared from tin and lead alloy 63% tin,
37% lead).​

Answer 1

1.   Wires used in householdd are usually covered with materials like plastic or rubber, because plastic and rubber are bad conductors of electricity and do not allow current to flow. This prevents us from getting a shock due to a  short circuit.

2.Fuses are safety devices that are to be built into our electrical system. If there were no fuses and we operated too many appliances on a single circuit, the cable carrying the power for that circuit would get extremely hot, short circuit, and possibly start a fire. To prevent electrical overloads, fuses are designed to trip or blow, stopping the flow of current to the overloaded cable .Hence, A fuse wire is made of an alloy of lead and tin If the current in a circuit rises too high, the fuse wire melts.