Bernie

As has been indicated above, force is not a quantum mechanical quantity; instead, the quantity which should be preferred is the 'potential' (energy), as this doubtlessly exists in both worlds, the classical and the quantum domain. But still there is a paper from Feynman (I think his bachelor thesis!) with a proof that forces can be derived even in the quantum world. If you want to be very accurate you should consider that the distance r between the electron and the proton varies with time. Quantum mechanics tells us, that the electron can be found statistically in the range around the Bohr radius a0; to be exact: the most probable separation is the Bohr radius a0, wheras the mean (average) separation is 1.5 a0.