# Q. A current of 2 mA was passed through an unknown resistor which dissipated a power of 4.4 W. Dissipated power when an ideal power supply of 11V is connected across it is :

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Solution:

## $P -I^{2}R$ $4.4 = 4\times10^{-6}R$ $R = 1.1 \times10^{6} \Omega$ $P' =\frac{11^{2}}{R} = \frac{11^{2}}{1.1} \times 10^{-6} = 11 \times10^{-5} W$

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