Fifty electric bulbs, all identical, are connected in series across the mains of a 220 V supply. After one bulb is fused, the remaining 49 bulbs connected in series across the same mains. The illumination will be

Question

Dr. Abubacker · Accepted Answer

(d) If resistance of each bulb be $R$, then bias voltage $V$ is same in both cases, hence $P = \frac{v^{2}}{R_{total}}$
In the case $R_{total} = 50R\ and\ in\ second\ case\ 49\ R$
$	herefore\frac{P_{1}}{P_{2}} = \left( \frac{49}{50} ight)^{2} \Rightarrow P_{2} = \left( \frac{50}{49} ight)^{2}.P_{1}$
or $P_{2} > P_{1}$

Q. Fifty electric bulbs, all identical, are connected in series across the mains of a 220 V supply. After one bulb is fused, the remaining 49 bulbs connected in series across the same mains. The illumination will be

Explanation

Reviewed by Dr. Abubacker

Want more practice?