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The formula of the Q-factor (quality factor) is Q= _______.

Asked in GSEB Board July 2021 · Power and bandwidth at resonance

Answer: (4) (ω₀L)/R

Step-by-step solution

The Q-factor of a series LCR circuit is Q=(ω₀L)/R, where ω₀=1/(√LC) is the resonant angular frequency.

ω₀L is the inductive reactance at resonance, in ohms, and R is in ohms, so Q is a pure number.

It can also be written Q=1/(ω₀CR)=1/R√L/C.

A smaller R gives a larger Q and a sharper resonance.

So Q=(ω₀L)/R.

Why the other options are wrong

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