Question

The expression of power (P1) at lower half power frequency is?

(a) (I^2maxR)/8

(b) (I^2maxR)/4

(c) (I^2maxR)/2

(d) I^2maxR

The question was posed to me by my college director while I was bunking the class.

Query is from Bandwidth of an RLC Circuit topic in section Resonance & Magnetically Coupled Circuit of Network Theory

Answer 1

Right choice is (c) (I^2maxR)/2

The explanation is: The upper and lower cut-off frequencies are sometimes called the half-power frequencies,. At these frequencies the power from the source is half of the power delivered at the resonant frequency. The expression of power (P1) at lower half power frequency is P1 = (I^2maxR)/2.