Physics
posted by Ashley .
A tennis ball with a speed of 5.0 m/s is thrown perpendicularly at a wall. After striking the wall, the ball rebounds in the opposite direction with a speed of 3.0 m/s. If the ball is in contact with the wall for 0.013 s, what is the average acceleration of the ball while it is in contact with the wall?

Ft = m(final velocity)  m(initial velocity)
F = ma so equation changes to
mat = m(final velocity)  m(initial velocity)
plug in values and solve for 'a'