Question

An electric bulb is rated at 220v-100w . if it is operated at 110 v then power consumed

Answer 1

You have to use the formula "P=IV" and answer is 50 watt

Answer 2

Answer:

first u have to find the first parts but by using the formula P=V2/R

Ist parts: V = 220V

P= V2/R

100 W= 220square/R

= 484 ohm

similarly,

V= 110V

powe consumed = V2/R

= 110 square/R

= 110 square/484

= 25 W