Solution:

In the following situations, an electrical device may cause an electric shock.

(i) If the fuse is placed in the neutral wire and an excessive current flows in the circuit due to a malfunction in the appliance. In this case, the fuse will burn out and the current will stop flowing in the circuit. However, the appliance is still linked to the supply’s high potential point through the live wire. In this circumstance, if a person touches the malfunctioning device. he will receive an electric shock since he will come into contact with the mains through the live wire.

The fuse must always be connected in the live wire as a precaution.

(ii) The appliance obtains the high potential of the live wire when the live wire of a malfunctioning appliance comes into direct contact with its metallic case due to a rupture in the insulation after prolonged usage. Because current passes through his body to the soil, a person contacting the appliance will receive a lethal shock.

Preventive measure: The electric appliance should be properly ‘earthed.’