A 44 mH inductor is connected to 220 V, 50 Hz AC supply. Determine the rms value of the current in the circuit. What is the net power absorbed over a complete cycle? Explain.
Given , inductance = 44 mH
= 44 x ${{10}^{-3}}$ H
${ V }{ rms }$ = 220 V
Frequency of inductor , v = 50 Hz
Inductive reactance , ${ X }{ L }$ = 2 $\pi$vL
= 2 x 3.14 x 50 x 44 x ${{10}^{-3}}$
= 13.82 Ω
The rms value of current in the circuit
${ I }{ rms }$ =
${ V }{ rms }$ / Xl = 220 / 13.82 = 15.9 Ω
Power absorbed , P = ${ V }_{ rms }$ Irms cos$\phi$
For pure inductive circuit , $\phi$ = 90°
P = 0
Thus, power spent in one half cycle is retrieved in the other half cycle.