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Question
If the current I through a resistor is increased by 100% (assume that temperature remains unchanged), the increase in power dissipated will be
Options
100%
200%
300%
400%
Solution
300%
Explanation -
If the current is increased by 100% then the current will become twice i.e 2I. The power dissipated through a resistor is given by
P = I2R
If the current is made twice then power dissipated will become four times.
i.e. P' = 4 P
The percentage increase in power is given as,
`"Increase in power" = (4"P" - "P")/"P" xx 100%`
= 300%
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