Question

Observe the following figure which bulb get fuse.

Answer 1

This question tests on the relationship between, power, current and voltage.

The formula connecting the three is as follows :

P = VI

P = Power in watts

V = Voltage in Volts.

I = Current in Amperes.

Given the voltage and power we can get the current.

We get them as follows :

1) 220V, 100W

I = 100/220 = 0.4545 A

2) 220 V, 50 W

I = 50/220 = 0.227 A

Given that the bulb with 50 W and 220 V has a lower current carrying capacity than the bulb having 100W and 220 V it will require a fuse so that it is not blown by the excess current from the bulb rated at 100 W.