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The resonance frequency of this RLC circuit is 88.9 Hz. The resistor value associated to critically damped oscillations is 71.6 Ohm. Just for convenience, the resistor at the bottom (probe) makes it up to 100 Ohm with the resistor of the series RLC. The Q factor is 0.5 (probe resistor not included). The amplitude of the input is 10 Volt oscillating at 88.9 Hz.
When the circuit is driven at the resonance frequency, the impedance of the series RLC is equal to R. If the switch in parallel with R is close, than the RLC impedance is zero.
The effect of zero impedance can be observed by looking at the voltage drop across the series RLC, which becomes zero after a short transient period.
For a negligible R, the series RLC is "totally transparent" to the signal oscillating at the resonant frequency.
### BONUS ###
At resonance, the voltage's magnitude across either L or C (5 V) is Q times the magnitude of the input voltage (10 V).
To observe "voltage magnification", close all switches but the one across R and wait for the transients to extinguish.
To observe critically damped oscillations, disconnect the series RLC from the input and open the switch in parallel with the resistor.
### WHAT TO REMEMBER ###
"Only the AC component of the input signal oscillating at the resonant frequency of the series RLC is allowed to go through the branch containing the series RLC itself."
To see this effect, change the frequency of the input signal and observe the magnitude of the voltage drop across the probe resistor, which will always be smaller with respect to the resonance case.
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