In an $ac$ circuit,the current lags behind the voltage by $\pi /3$. The components in the circuit are

When $80 \ V$ $d.c.$ is applied across a solenoid,a current of $0.8 \ A$ flows in it. When $80 \ V$ $a.c.$ is applied across the same solenoid,the current becomes $0.4 \ A$. If the frequency of $a.c.$ source is $50 \ Hz$,the impedance and inductance of the solenoid are nearly:

An $AC$ circuit has an inductor and a resistor of resistance $R$ in series,such that $X_L = 3R$. Now,a capacitor is added in series such that $X_C = 2R$. The ratio of the new power factor to the old power factor of the circuit is $\sqrt{5} : x$. The value of $x$ is ...... .

In an $L-R$ circuit,the inductive reactance is equal to $\sqrt{3}$ times the resistance $R$ of the circuit. An e.m.f. $E = E_0 \sin(\omega t)$ is applied to the circuit. The power consumed in the circuit is:

$A$ series $R-C$ circuit is connected to an alternating voltage source. Consider two situations:
$(a)$ When the capacitor is air-filled.
$(b)$ When the capacitor is mica-filled.
If the current through the resistor is $i$ and the voltage across the capacitor is $V$,then:

In the figure,if $A$ and $B$ are identical bulbs,which bulb glows brighter?