What will be the phase difference between virtual voltage and virtual current when current in the circuit is wattless?

A coil having an inductance of $$\frac{1}{\pi} \mathrm{H}$$ is connected in series with a resistance of $$300 \Omega$$. If $$20 \mathrm{~V}$$ from a $$200 \mathrm{~Hz}$$ source are impressed across the combination, the value of the phase angle between the voltage and the current is

An alternating voltage is applied to a series LCR circuit. If the current leads the voltage by $$45^{\circ}$$, then $$\left(\tan 45^{\circ}=1\right)$$

For a purely inductive or a purely capacitive circuit, the power factor is