A series LRC circuit is driven by an ideal sinusoidal AC voltage generator with a peak emf of 12 V.If L = 30.0 mH,R = 200 ohms,and C = 0.040 mF,what is the average power dissipated in the resistor if the circuit is driven at a frequency equal to ten times the resonance frequency?
A)0.013 W
B)0.016 W
C)0.21 W
D)0.36 W
E)0.72 W

Question

Quizplus · Accepted Answer

The average power dissipated in the resistor is given by P_avg = (V_rms^2 * R) / Z^2, where Z is the impedance. At a frequency ten times the resonance frequency, the impedance is dominated by the inductive and capacitive reactances, which are equal and opposite, leading to Z ≈ R. Therefore, P_avg = (12/√2)^2 / (2R) = 0.013 W.

A Series LRC Circuit Is Driven by an Ideal Sinusoidal