Question

An electric bulb is rated 220V and 100W. When it is operated on 110V, then the power consumed will be ?
If we do it with P=V×I we are getting 50W

Answer 1

When bulb is rated 220V and 100W then

Current,I = P/V

= 100W/220V

=10/22 A

Now, if current,I is 10/22 A, and potential difference is 110V then,

Power, P = V × I

= 110V × 10/22 A

= 1100/22

= 50 W

So your answer is correct. I hope it helps