Question

A fuse has a current rating of $5A$. Can it be used for a heater of rating $1kW,220V$ ?

Answer 1

Step 1: Given data:

Power of the heater, $P=1kW=1000Watt$

Operating at voltage, $V=220V$

Current rating of fuse =$5A$

Step 2: Calculating current ($I$)

We know that, $I=\frac{P}{V}$

Thus, $I=\frac{P}{V}=\frac{1000}{220}=4.54A$

Hence, a fuse of current rating $5A$can be used as it has a slightly greater rating than the current flowing through the circuit.