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if the electrc current in a lamp decreas...

if the electrc current in a lamp decreases by `5%` then the power output decreases by

A

`20%`

B

`10%`

C

`5%`

D

`2.5%`

Text Solution

Verified by Experts

The correct Answer is:
B
`P= i^(2)R prop P prop i`
`rArr (DeltaP)/(P) xx 100 = 2xx (DeltaI)/(I)xx100`
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