Fill in the following blanks with suitable words:

(a) A fuse should always be placed in the ........... wire of a mains circuit. (b) The earth wire should be connected to the ........... of an appliance.

(a) A fuse should always be placed in the live wire of a mains circuit.

The fuse wire is always connected to the live wire of the main circuit because if the fuse is connected to the neutral wire, then due to the excessive current flowing when the fuse burns the current stops flowing in the circuit, but the appliance remains connected to the high potential point of the supply through the live wire. Now if someone touches the device, he/she can get a shock as the person will come in contact with the live wire through the appliance.

(b) The earth wire should be connected to the metal case of an appliance.

To avoid the risk of the electric shock, the metal body of an electrical appliance is 'earthed' or 'grounded'. Earthing means connecting the metal case (or metal body) of an electrical appliance to the earth through a metal wire called 'Earth Wire'.

The electric wiring in houses, shops, or factories has three wires: live, neutral and earth. The first two carry electric current from the power station and the third is earthed by connecting it to the earth through a metal wire called 'Earth Wire'.

Metallic bodies of electric appliances such as refrigerator, electric irons, televisions are connected to the earth wire so that when any fault occurs or the live wire touches the metallic body the charge flows to the earth without damaging the appliance and without causing any injury to the humans.