[Déjà Bru]

Originally Posted by kq76

The speed of the ball coming in does contribute to the exit velocity. It's known as energy transfer. So basically the ball coming in has its own energy, but when the ball is hit and redirected, that old energy doesn't all disappear in an instant, some of it gets redirected. EDIT: It doesn't add that much, however, a lot of the energy is lost in impact. Bat speed plays a much bigger role. There's even a known formula for it. I like how one professor put it, 85% comes from bat speed, 15% from pitch speed.

There are lots of cool videos on all sorts of science to do with baseball. Just search for "physics / science of baseball".

Interesting, thanks.