Electrical & Computer
RLC Resonance Lab
At resonance the inductor and capacitor reactances cancel exactly, so the series RLC circuit looks purely resistive — the impedance bottoms out at R and the current peaks. This lab plots the current-versus-frequency response on a log axis, marks the resonant frequency f₀ = 1/(2π√(LC)), and shades the half-power (−3 dB) band whose width is the bandwidth Δf = f₀/Q. The quality factor Q = (1/R)√(L/C) sets how sharp and selective the peak is: drop R and the curve spikes into a narrow, high-Q resonance; raise it and the peak flattens. A swept dot reports the live current and phase, which crosses zero exactly at resonance — leading below it (capacitive) and lagging above (inductive). It is the intuition behind every radio tuner and band-pass filter.
5.03 kHz
Resonance f₀
3.16
Quality factor Q
1.59 kHz
Bandwidth Δf
500.00 mA
Peak current
0 Hz
Sweep f
0°
Phase
0 A
Current at sweep
A series RLC peaks at f₀ = 1/(2π√(LC)), where the inductor and capacitor reactances cancel and only R limits the current. The sharpness is Q = (1/R)√(L/C); the −3 dB band (shaded) has width Δf = f₀/Q. Lower R → higher Q → a sharper, more selective peak.
How to use this simulation
At resonance the inductor and capacitor reactances cancel exactly, so the series RLC circuit looks purely resistive — the impedance bottoms out at R and the current peaks. This lab plots the current-versus-frequency response on a log axis, marks the resonant frequency f₀ = 1/(2π√(LC)), and shades the half-power (−3 dB) band whose width is the bandwidth Δf = f₀/Q. The quality factor Q = (1/R)√(L/C) sets how sharp and selective the peak is: drop R and the curve spikes into a narrow, high-Q resonance; raise it and the peak flattens. A swept dot reports the live current and phase, which crosses zero exactly at resonance — leading below it (capacitive) and lagging above (inductive). It is the intuition behind every radio tuner and band-pass filter.
Everything runs in your browser — no sign-up, no download. Change a value and the result updates instantly, so you can build a feel for how each input shapes the outcome. It pairs with Crameleon's practice exams and step sheets when you want to go from intuition to working the problems.