An $$R-L-C$$ circuit consists of a $$150 \Omega$$ resistor, $$20 \mu \mathrm{F}$$ capacitor and a 500 mH inductor connected in series with a 100 V AC supply. The angular frequency of the supply voltage is $$400 \mathrm{rad} \mathrm{s}^{-1}$$. The phase angle between current and the applied voltage is

Capacitive reactance of a capacitor in an AC circuit is $$3 \mathrm{k} \Omega$$. If this capacitor is connected to a new AC source of double frequency, the capacitive reactance will become.

A coil of inductance 0.1 H and resistance $$110 \Omega$$ is connected to a source of 110 V and 350 Hz . The phase difference between the voltage maximum and the current maximum is