Question

State the role of an electric fuse, used in series with an electrical appliance. Why should in an electric circuit a fuse with defined rating not be replaced by one with a larger rating?

Hint:

A fuse should always be replaced with one having the same rating to ensure that the appliance is protected from overloads.

Answer 1

The role of an electric fuse is to protect the electrical circuit and appliances from damage caused by excess current. A fuse is a safety device that is connected in series with the electrical appliance. It is made of a wire with a low melting point, and if the current exceeds a certain threshold, the wire melts, thus breaking the circuit and preventing damage to the appliance. 
Why should a fuse with a defined rating not be replaced by one with a larger rating? 
A fuse is designed to melt and break the circuit if the current exceeds a certain safe value for the appliance. If a fuse with a larger rating is used, it will not melt and break the circuit at the right time. This can lead to overheating of the wires and components, potentially causing fires or damaging the appliance. Using a larger-rated fuse will not protect the appliance as intended, as it will allow excessive current to flow without interrupting the circuit.