If the power factor in a circuit is unity,then the impedance of the circuit is

$A$ circuit,consisting of an inductance and a resistance in series,is connected to a $250 \ V$ $A$.$C$. supply. It draws a current of $10 \ A$. If the power consumed in the circuit is $1500 \ W$,calculate the wattless current. (in $A$)

$A$ capacitor $C = 2 \mu F$ and an inductor with $L = 10 H$ and coil resistance $R = 5 \Omega$ are connected in series in a circuit. When an alternating current of $r.m.s.$ value $I_{rms} = 2 A$ flows in the circuit,the average power in watts in the circuit is:

The $r.m.s.$ current in an $ac$ circuit is $2 \ A$. If the wattless current is $\sqrt{3} \ A$,the power factor is:

For the series $LCR$ circuit connected with a $220 \ V$, $50 \ Hz$ a.c. source as shown in the figure, the power factor is $\frac{\alpha}{10}$. The value of $\alpha$ is . . . . . .

An alternating voltage of $V = V_{0} \sin \omega t$ is applied across a circuit. As a result, a current $I = I_{0} \sin (\omega t - \frac{\pi}{2})$ flows in it. The power consumed per cycle is . . . . . . .