Q. 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 :
A) 0.5
B) 1.0
C) -1.0
D) zero
Explanation
[Solution] Equal phase angles imply $X_L = X_C$, so the full circuit is at resonance and the power factor is 1. Answer (2).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.