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 ``\frac{\pi}{3}``. If instead C is removed from the circuit,
the phase difference is again
``\frac{\pi}{3}`` between current
and voltage. The power factor of the circuit is :
(1) zero
(2) 0.5
(3) 1.0
(4) -1.0