1. Yes, there were a typing error in Q=V*C; luckilly dividing by C=1 gives
the same result at multiplying.
2. I agree that "piece-wise exponential" is a poor term. The curve can as
well be called "piece-wise" linear, "piece-wise" hyperbolic, etc. The
impotrant point is that it is not a straight line on the semi-log plot
over the entire region of I.
Ludwik Kowalski