This is an RLC circuit, which is an oscillating circuit consisting of a resistor, capacitor, and inductor connected in series. The capacitor is charged initially; the voltage of this charged capacitor causes a current to flow in the inductor to discharge the capacitor. Once the capacitor is discharged, the inductor resists any change in the current flow, causing the capacitor to be charged again with the opposite polarity. The voltage in the capacitor eventually causes the current flow to stop and then flow in the opposite direction. The result is an oscillation, or resonance.

The voltages and currents in the inductor, capacitor, and resistor are shown in the scopes below the circuit (voltage is shown in green, current in yellow). The resonance frequency depends on the capacitance and inductance in the circuit and is shown in the lower-right corner (as res.f).

After a while, the oscillation will die down, because of the resistor. Close the switch momentarily to get it going again.

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