Question

In a series LCR circuit R = 200 W and the voltage and the frequency of the main supply is 220 V and 50 Hz respectively. On taking out the capacitance from the circuit the current lags behind the voltage by 30°. On taking out the inductor from the circuit the current leads the voltage by 30°. The power dissipated in the LCR circuit is

(1) 305 W

(2) 210 W

(3) Zero W

(4) 242 W

Answer 1

Correct Option(4) 242 W

Explanation:

The given circuit is under resonance as X_L = X_C.

[same phase change in L-R and C-R circuiis]

Hence, the power dissipated in the circuit is

P=V²/R=242W