LC Resonant Frequency Calculator Formula

Understand the math behind the lc resonant frequency calculator. Each variable explained with a worked example.

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Formulas Used

Resonant Frequency

resonant_freq = 1 / (2 * pi * sqrt(inductance * 1e-3 * capacitance * 1e-6))

Angular Frequency

angular_freq = 1 / sqrt(inductance * 1e-3 * capacitance * 1e-6)

Variables

VariableDescriptionDefault
inductanceInductance(mH)10
capacitanceCapacitance(μF)100

How It Works

LC Resonant Frequency

An LC circuit oscillates at a natural frequency determined by the inductance and capacitance.

Formula

f = 1 / (2*pi*sqrt(L*C))

At resonance, the inductive and capacitive reactances are equal and cancel, leaving only resistance to limit current.

Worked Example

An LC circuit with L = 10 mH and C = 100 μF.

inductance = 10capacitance = 100
  1. 01f = 1 / (2*pi*sqrt(L*C))
  2. 02f = 1 / (2*pi*sqrt(10e-3 * 100e-6))
  3. 03f = 1 / (2*pi*sqrt(1e-6))
  4. 04f = 1 / (2*pi*0.001)
  5. 05f = 1 / 0.006283 = 159.15 Hz

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