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 :

An inductor 20 mH, a capacitor 100 $$\mu $$F and a resistor 50 $$\Omega $$ are connected in series across a source of emf, V = 10 sin 314 t. The power loss in the circuit is