Question

A geyser has the rating 2000 W-220 V marked on it. What should be the minimum current rating of the fuse wire to be used?

Answer 1

We know that, $P=VI\Rightarrow I=\frac{P}{V}=\frac{2000}{220}=9.09A$
The fuse rating should be slightly greater than the rated current. So we can choose a fuse of 10 A rating.