Question #46f0c

1 Answer
May 22, 2016

4.69×1014MeV and λ=2.24×1034m

Explanation:

a quick search in the internet suggests that Federer's average first serve at Wimbledon was about 115 mph in 2016 which is about 51 m/s.

The mass of a tennis ball is about 58g (0.058kg).

So the kinetic energy would be KE=12mv2=120.058512=75J

An electron volt = 1.6×1019J and a MeV = 1.6×1013J

So in MeV, the energy would be 751.6×1013=4.69×1014MeV

The de Boglie wavelength,λ is given by λ=hmv
So λ=6.63×10340.05851=2.24×1034m