In an $A.C.$ circuit,the instantaneous $e.m.f.$ and current are given by:
$e = 100 \sin(20t)$
$i = 20 \sin(30t - \frac{\pi}{4})$
In one cycle of $A.C.$,the average power consumed by the circuit and the wattless current are,respectively:

In an electrical circuit,$R, L, C$ and an $a.c.$ voltage source are all connected in series. When $L$ is removed from the circuit,the phase difference between the voltage and the current in the circuit is $\pi /3$. If instead,$C$ is removed from the circuit,the phase difference is again $\pi /3$. The power factor of the circuit is

In the circuit shown in the figure,the $ac$ source gives a voltage $V = 20\cos(2000t)$. Neglecting source resistance,the voltmeter and ammeter readings will be:

If the input voltage $V_i$ to the circuit below is given by $V_i(t) = A \cos (2 \pi f t)$ and the output voltage is given by $V_o(t) = B \cos (2 \pi f t + \phi)$,which one of the following four graphs best depicts the variation of $\phi$ versus $f$?

In an $A.C.$ circuit,the current:

At very high frequencies, the current $(i)$ in the given circuit is (in $A$)