What is the maximum number of 60 W bulbs that can be run from the mains supply of 220 volts if you do not want to overload a 5 A fuse?
Let us assume the number of bulbs be y.
Power of y bulbs, P=60y
V=220V, I=5A
We know that
P = VI
60y = 220 x 5
60y = 1100
y=18.33
So, number of bulbs required are 18.