The thing is, they use this direction for current flow to derive the equation
$-iR-\frac{q}{c}=0$ and then derive the equation $q(t)=Q_o e^\frac{-t}{RC}$ from the differential equation $\frac{dq}{dt}=\frac{-q}{RC}.$
This seems pretty artifical to me, because if I use the other direction for current, which seems more natural to me, I don't get the same equation for $q(t)$. Any ideas?
Another thing which seems artificial is that their equation produces a "negative current" which is really just there to satisfy the =0 equality. And which means, and wrongly, that the resistor is giving energy to the system and not the exterior. (That's what I think, I may be wrong).
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