First applying Kirchhoff's loop rule with an ideal emf device with potential difference V, a capacitor with capacitance C, and a resistor with resistance R, you get:(adsbygoogle = window.adsbygoogle || []).push({});

V - q/C - iR = 0 or V = q/C + dq/dt*R

For charging a capacitor. This makes sense. But for a discharging capacitor in the same circuit but without the emf device, you have the differential equation: q/C + dq/dt*R = 0

But this makes no sense to me. The current is in the other direction when the capacitor is being discharged. The higher potential side marks the direction of that current. That being said, applying Kirchhoff's loop rule, you end up with -iR + q/C = 0 which is not the same.

Am I applying the rule incorrectly?

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# Homework Help: Discharging capacitor, the differential equation

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