Q 12-03-304JEE MainJEE Main 2025 (4 Apr, Shift 2)Easy
There are $n$ identical electric bulbs, each designed to draw a power $p$ independently from the mains supply. They are now joined in series across the mains supply. The total power drawn by the combination is:
Answer: (C) $\dfrac pn$
Each bulb has resistance $R = \dfrac{V^2}{p}$. In series the total resistance is $nR$, so across the same supply
$$P = \frac{V^2}{nR} = \frac pn$$
(assuming the resistance of each bulb does not change).
Solution by Sreeraj P, M.Sc Physics