FullCalculator

Resonant Frequency Calculator

Find Resonant Frequency

f = 1 / (2π√(LC))

Find Required Capacitance

C = 1 / (4π²f²L)

Find Required Inductance

L = 1 / (4π²f²C)

Formula

f = 1 / (2π√(LC)) | C = 1 / (4π²f²L) | L = 1 / (4π²f²C) | ω₀ = 1 / √(LC)

Frequently Asked Questions

What is resonant frequency?
The resonant frequency of an LC circuit is the frequency at which the inductive and capacitive reactances are equal and cancel each other out. At resonance, the circuit impedance is purely resistive, and energy oscillates between the inductor's magnetic field and the capacitor's electric field.
What is a tank circuit?
A tank circuit (or LC circuit) consists of an inductor and capacitor connected in parallel or series. At resonance, it stores energy by oscillating it between the inductor and capacitor. Tank circuits are used in radio transmitters, receivers, filters, and oscillators.
What determines the bandwidth of an LC circuit?
The bandwidth is determined by the Q factor (quality factor): BW = f₀/Q. The Q factor depends on the resistance in the circuit: Q = (1/R)×√(L/C) for series, or Q = R×√(C/L) for parallel. Higher Q means narrower bandwidth and sharper tuning.

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