physics

[Addison]

a 2.5 kg ball strikes a wall with a velocity of 8.5 m/s to the left. The ball bounces off with a velocity of 7.5 m/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?

[chroot]

Does this help?

http://hyperphysics.phy-astr.gsu.edu/hbase/impulse.html

- Warren

[HallsofIvy]

Momentum to the left, before the collision, is (- 8.5m/s)(2.5 kg) (negative because it is to the left). Momentum to the right, after the collision is (7.5 m/s)(2.5kg). Change in momentum is the difference between those: (7.5 m/s)(2.5kg)+(8.5m/s)(2.5 kg).
Since that took place in 0.25 s, the average rate of change of momentum is that divided by 0.25 s. Force IS rate of change of momentum.