Current Electricity 5 Question 18
18. A $25 W$ and a $100 W$ bulb are joined in series and connected to the mains. Which bulb will glow brighter?
(1979)
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Solution:
- In series current is same. Therefore, from the relation $P=i^{2} R$, a bulb having more resistance consumes more power or glows brighter. $25 W$ bulb has more resistance $R=\frac{V^{2}}{P}$ compared to $100 W$ bulb. Hence, it will glow brighter.
