Question
A virtual current of 4 A flows in a coil when it is connected in a circuit having a.c. of frequency 50 Hz. The power consumed in the coil is 240 W. Calculate the inductance of the coil if the virtual p.d. across it is 100 V.

0.0545 H

0.0637 H

0.6545 H

None of these
medium
Solution
0.0637 H
Let L be the inductance, R the resistance and Z the impedance of the coil. The power is consumed in R only. Thus, the average power is
Here,
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