RC Circuit Simulator

Observe the exponential charge and discharge curves with an explicit capacitor-voltage and current sign convention.

+-12V10kΩ++ Q-- Q100μF[PAUSED]I reference
Time Const (τ) = R × C = 1.00s
Vcapacitor = 0.00 V (0.0%)
Current (I) = (Vs - Vc) / R = (12V - 0.00V) / 10kΩ = 1.200 mA
Sign convention: positive current charges the capacitor from the source; negative current means the capacitor is discharging energy back through the resistor.

Legend

→
Current referenceThe arrow shows the positive current direction used in the RC equations; the arrow flips during discharge.
+ / -
Capacitor polarityThe capacitor voltage is defined positive from the upper plate to the lower plate.
Q
Charge markersThe colored plate fills indicate relative stored charge magnitude, not a literal surface-charge map.