1. What is the quality factor (Q) in an a.c. circuit?

Dear Student,
The quality factor (Q) in an ac circuit is a parameter which established a relationship between energy stored by the circuit to the energy dissipated by it. It is the ratio of the maximum energy stored in the circuit due to its reactance to the energy dissipated due to its resistance during each cycle of oscillation. It is a ratio of resonant frequency to bandwidth and is expressed as:
$Q = \frac{{ƒ}_r }{BW}$

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