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 $\frac{\pi}{3}$. If instead ' $C$ ' is removed from the circuit, the phase difference is again $\frac{\pi}{3}$. The power factor of the circuit is $\left(\tan \frac{\pi}{3}=\sqrt{3}\right)$

In series LCR resonant circuit, R $=800 \Omega$, $\mathrm{C}=2 \mu \mathrm{~F}$ and voltage across resistance is 200 V . The angular frequency is $250 \mathrm{rad} / \mathrm{s}$. At resonance, the voltage across the inductance is

If maximum energy is stored in a capacitor at $\mathrm{t}=0$ then the time after which, current in the circuit will be maximum is

In LCR series circuit, R = 18 $\Omega$ and impedance $33 \Omega$. An r.m.s. voltage of 220 V is applied across the circuit. The true power consumed in a.c. circuit is