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RC / RLC Circuit Lab

Learning goal

Two behaviors that rule all of circuit dynamics: the exponential (RC charging, time constant \(\tau = RC\)) and the resonance peak (series RLC, \(f_0 = 1/2\pi\sqrt{LC}\), sharpness set by \(Q = \omega_0 L/R\)).

Things to try

  1. RC tab: double \(R\), then double \(C\) — same stretch of \(\tau\) either way. Why does only the product matter?
  2. Find settings where the capacitor is "fully" charged within 100 ms. (Rule of thumb: \(5\tau\).)
  3. RLC tab: lower \(R\) and watch the peak sharpen — high-\(Q\) tuning. This curve is how a radio picks one station out of the spectrum.
  4. Double \(L\) and halve \(C\): the resonance stays put but the peak narrows — \(f_0\) depends on \(LC\), \(Q\) on \(\sqrt{L/C}/R\).

RC circuits · DC circuits · Faraday's law & inductance