OK - I'm working on Toricelli's Principle at the moment. That is, a tank where theres a small hole at the bottom and we're supposed to plot h (height) vs. t (time), V_jet vs. t, mass flow rate vs. t, and change in height vs. t. Now - I get a linear graph for V_jet and mass flow rate vs. time, but a non-linear curve for h and mass in the tank vs time. And I can't prove it. We're neglecting any internal energy transfers, etc. just plain old V = Sqrt(2.g.h) Any help muchly appreciated.