Q. Two electric bulbs $A\ and\ B$ are rated as 60 W and 100 W. They are connected in parallel to the same source. Then
A) $B$ draws more current than $A$
B) Currents drawn are in the ratio of their resistances
C) Both draw the same current
D) $A$ draws more current than $B$
Explanation
(a) The power drawn by the bulb is
$\ \ \ \ \ P = \frac{V^{2}}{R}$
$\Rightarrow R = \frac{V^{2}}{P}$
or $R \propto \frac{1}{P}$
(as $V$ is same in parallel)
It means that greater power will have less resistance and therefore, draws more current. Hence, current flowing in bulb $B$ will be more.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.