A series LCR circuit containing 5.0 H inductor, 80$$\mu$$F capacitor and 40$$\Omega$$ resistor is connected to 230V variable frequency ac source. The angular frequencies of the source at which power transferred to the circuit is half the power at the resonant angular frequency are likely to be :

A 40 $$\mu $$F capacitor is connected to a 200 V. 50 Hz ac supply. The rms value of the current on the circuit is, nearly :

A series LCR circuit is connected to an ac voltage source. When L is removed from the circuit, the phase difference between current and voltage is $${\pi \over 3}$$. If instead C is removed from the circuit, the phase difference is again $${\pi \over 3}$$ between current and voltage. The power factor of the circuit is :

The magnetic potential energy stored in a certain inductor is 25 mJ, when the current in the inductor is 60 mA. This inductor is of inductance