# Illustration Current-time graph - discharging a capacitor

When discharging the capacitor in a RC circuit, a discharge current $$I(t)$$ flows. The current starts at the value $$-I_0$$ and decreases exponentially to zero:$$I(t) ~=~ -I_0 \, \mathrm{e}^{-\frac{t}{R\,C}}$$
Here $$C$$ is the capacitance of the capacitor and $$I_0 = \frac{|U_0|}{R}$$ is the initial current at time $$t = 0$$.