A coil offers a resistance of $$20 \mathrm{~ohm}$$ for a direct current. If we send an alternating current through the same coil, the resistance offered by the coil to the alternating current will be :

The capacitance of a parallel plate capacitor is $$400 \mathrm{~pF}$$. It is connected to an ac source of $$100 \mathrm{~V}$$ having an angular frequency $$100 \mathrm{~rad~s}^{-1}$$. If the rms value of the current is $$4 \mu \mathrm{A}$$, the displacement current is:

The instantaneous values of alternating current and voltages in a circuit given as

$$\begin{aligned} & i=\frac{1}{\sqrt{2}} \sin (100 \pi t) \mathrm{amp} \\ & e=\frac{1}{\sqrt{2}} \sin (100 \pi t+\pi / 3) \text { volt } \end{aligned}$$

The average power (in watts) consumed in the circuit is

In the series L-C-R circuit shown, the impedance is