A tennis racket is in contact with a 55 kg ball for 0.0050 s changes the ball's velocity from 30 m/s [E] to 40 m/s [W] over a distance of 0.0001 m. how much work is done on the tennis ball by the racket?

Answer 1

Force*distance=work

but force*time=mass*changevelocity
or force= 55*(70)/.0050 Notice the 70 as change of velocity, figure that out.

One remark: I would hate to hit a 55kg ball, geepers, that is bigger than some of my high school students.

Put that force into the first work equation.