One question I have is that while part of the energy goes into the rotation, which causes a pressure differential and a net downward force in addition to gravity (and so a higher incident speed at bounce), would the same higher incident speed be achieved by a flatter shot which did not put energy into rotation in the first place?
In other words, if Karlovic hit a flat serve and achieved a certain incident speed at bounce, and then hit a topspin serve with lower speed towards the target, could the two incident speeds at bounce be the same? The input "energy" is assumed to be the same in both cases i.e. Ivo spends the same number of calories for each.
To me it seems the flat serve will have a faster incident speed, even though the topspin serve might descend from a higher height and have the Magnus force pushing down too. What do you think?
Last edited by sureshs : 12-01-2012 at 12:29 PM.