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 isA. `10%`B. `20%`C. `2.5%`D. `5%`

If voltage across a bulb rated 220 volt-100 watt drops by `2.5 %` of i

1.	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 isA. `10%`B. `20%`C. `2.5%`D. `5%`
Answer» Correct Answer - D (d) Power consumed `P = (V^(2))/(R )`. For small variation `100 xx (Delta P)/(P) = 2 (Delta V)/(V) xx 100 = 2 xx 2.5 %` Therefore, power would decrease by `5%`

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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 isA. `10%`B. `20%`C. `2.5%`D. `5%`

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