Q. 124.4( 45 Votes )
If the current I through a resistor is increased by 100% (assume that temperature remains unchanged), the increase in power dissipated will be
A. 100 %
B. 200 %
C. 300 %
D. 400 %
Case 1: power is given by
Case 2: when current is increased by 100%
It means that current becomes doubled i.e. 2I
Power will be P2 = (2I)2R
i.e. Power = 4 I2R
Change in dissipated power = 4 I2R- I2R =3 I2R
Increase in percent of power dissipated = 3P1/P1 ×100% = 300%
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