@FiReFTW @Hmgraphite1 @Kevo
The physics tells us that there is a very high rate of spin where a tennis ball, theoretically, can have a greater horizontal speed (
horizontal component of velocity) after the bounce than prior to the bounce. However, I don't believe that these conditions have ever been met in the real world on the tennis court. According to the calculations, for a given set of conditions in the
Scientific American article below, a topspin ball would need to exceed
7200 RPM (120 revs/second) in order to see an increase in horizontal speed. The fastest spin rates observed in tennis -- Nadal (topspin Fh), Sampras (2nd serve), Federer (Bh slice) -- have been around
5200 RPM, possibly 5400 RPM. I believe that
@JohnYandell can confirm this observed spin rate.
I don't believe that there are any conditions where the
total speed of the ball after a bounce will equal or exceed its speed prior to the bounce.
https://www.scientificamerican.com/article/experts-tennis-topspin-ball/