Q7.20 (b) A series LCR circuit with , , is connected to a variable frequency supply.
What is the source frequency for which average power absorbed by the circuit is maximum. Obtain the value of this maximum power.
Since the resistor is the only element in the circuit which consumes the power, the maximum absorbed power by circuit will be maximum when power absorbed by the resistor will be maximum. power absorbed by the resistor will be maximum at when current is maximum which is the natural frequency case,
Hence when source frequency will be equal to the natural frequency, the power absorbed will be maximum.
Hence frequency
Maximum Power Absorbed
.