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If voltage across a bulb rated 220 volt-...

If voltage across a bulb rated 220 volt-100 watt drops by `2.5 %` of its value, the percentage of the rated value by which the power would decrease is

A

0.05

B

0.1

C

0.2

D

0.025

Text Solution

Verified by Experts

`P prop V^(2)` So `(Deltap)/(P)=2(DeltaV)/(V)=5%`
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