Posted by Sarah on .
A 2.5kg ball strikes a wall with a velocity of 8.5m/s to the left. The ball bounces off the wall with a velocity of 7.5m/s to the right. If the ball is in contact with the wall for .25s, what is the constant force exerted on the ball by the wall?

Physics 
Andrew,
calculate change in the momentum. remember that after it experiences this "perfectly elastic collision" it has a negative velocity. Therefore the change in momentum would be p = absm1v1 + m2v2
change in momentum p = Ft
Force would be the average force or in this case the constant force