I need help with a problem

1. Apr 1, 2006

smbascug

A 0.145-kg baseball traveling 35.0 m/s strikes the catcher's mitt which, in bring the ball to rest, recoils backward 11.0 cm. What was the average force applied by the ball on the glove?

Can someone show me a formula for this problem or a way to solve this problem?? Please and Thank You

2. Apr 1, 2006

nrqed

In this example, you may use that the change of kinetic energy is equal to the average force times the distance over which the force acts (this is a special case of the work energy theorem, It is that simple here because no other force does any work. For example gravity does not do any work because the height of the baseball does not change)

Patrick

3. Apr 2, 2006

topsquark

Another way, and a good practice: Whenever you see the term "average force" think of the impulse-momentum theorem: $$m \Delta v = \bar F \Delta t$$.

-Dan