Charging and discharging a capacitor – measuring the RC time constant

PhysicsElectricity & CircuitsAges 16–17

A virtual lab circuit with a source of EMF E, a resistor R, a capacitor C and a two-way switch K: move K to 1 to charge the capacitor and to 2 to discharge it through R. A voltmeter reads u_C, the u_C(t) graph is plotted live, and the moment u reaches the 63% level is marked automatically so τ can be measured and compared with τ = RC. A data table records t, u_C, i, the charge q = Cu and the stored energy W = Cu²/2.