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

An electric fuse safeguards electrical circuits and devices from excessive current. This safety mechanism, connected in series, utilizes a wire with a low melting point. When the current surpasses a predefined limit, the wire melts, breaking the circuit and preventing damage.
Why is it crucial to avoid replacing a fuse with a higher rating? 
Fuses are engineered to open the circuit when current exceeds a safe threshold. A higher-rated fuse won't react promptly. Consequently, wires and components can overheat, potentially causing fires or damaging the appliance. A larger-rated fuse compromises the intended protection, permitting excessive current flow without interruption.