A coil has resistance of 20 W and inductance of 0.35 H. Compute its reactance and its impedance to an alternating current of 25 cycles/s.

Explanation:

Given;

Resistance of the coil, R = 20 W

Inductance of the coil, L = 0.35 H

Frequency of the alternating current, F = 25 cycle/s

Reactance of the coil is calculated as;

2πFL

Substitute in the given values and calculate the reactance

2π(25)(0.35)

= 55 W

Impedance of the coil is calculated as;

Therefore, the reactance of the coil is 55 W and Impedance of the coil is 59 W

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