Q. Two electric bulbs marked $25W - 220V$ and $100W - 220V$ are connected in series to a $440V$ supply. Which of the bulbs will fuse
A) Both
B) 100 $W$
C) 25 $W$
D) Neither
Explanation
(c) Resistances of both the bulbs are
$R_{1} = \frac{V^{2}}{P_{1}} = \frac{220^{2}}{25}$
$R_{2} = \frac{V^{2}}{P_{2}} = \frac{220^{2}}{100}$
$\therefore R_{2} > R_{2}$
Hence $25\ W$ bulb will fuse
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.