🔋 Capacitor Charge / Discharge

RC circuit, time constant τ = RC, charge vs time curve
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RC Circuit Controls

Live Outputs

Time Constant τ
10.0 s
Elapsed Time
0.00 s
V_C(t)
0.00 V
Current I(t)
0.00 mA
Charge Q(t)
0.00 mC
% Charged
0 %
V_C = V₀(1 − e^{−t/RC}) [charge]
V_C = V₀ · e^{−t/RC} [discharge]
τ = RC  |  I = (V₀/R)e^{−t/RC}

Circuit Diagram

V_C vs Time Graph

Time Constant τ = RC: After 1τ the capacitor reaches 63.2% of full charge. After 5τ it is considered fully charged (99.3%). The exponential curve is characteristic of all RC circuits. Larger R or C gives a longer time constant and slower charge/discharge.