Q12 of 35 Page 90

If the current I through a resistor is increased by 100% (assume that temperature remains unchanged), the increase in power dissipated will be

Case 1: power is given by


P1= I2R


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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