What is the resonant frequency in an electrical circuit?

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Multiple Choice

What is the resonant frequency in an electrical circuit?

Resonance occurs when the inductive and capacitive reactances balance each other out, so they cancel and the circuit behaves as if only resistance remains. In a series RLC circuit this makes the impedance reach its minimum and the current reach its maximum, while in a parallel RLC circuit the impedance is at its maximum. At this frequency the voltage and current are in phase, giving the best (near unity) power factor. Therefore the correct description is the frequency at which the capacitive reactance equals the inductive reactance. This frequency is also given by f0 = 1/(2π√(LC)). The other statements don’t describe resonance: it’s not simply the highest or lowest passing frequency, and the power factor is not at a minimum at resonance.

Resonance occurs when the inductive and capacitive reactances balance each other out, so they cancel and the circuit behaves as if only resistance remains. In a series RLC circuit this makes the impedance reach its minimum and the current reach its maximum, while in a parallel RLC circuit the impedance is at its maximum. At this frequency the voltage and current are in phase, giving the best (near unity) power factor. Therefore the correct description is the frequency at which the capacitive reactance equals the inductive reactance. This frequency is also given by f0 = 1/(2π√(LC)). The other statements don’t describe resonance: it’s not simply the highest or lowest passing frequency, and the power factor is not at a minimum at resonance.

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