Posted by: SteveT () on Mon Jan 10 09:17:42 2000

Hi Skipper,

First off, no, A is not equal to V. That's where you went wrong in the first place!! A is equal a CHANGE in V (A=dV) Sure there WAS acceleration to get the bat to hitting speed, but it was before the impact. Remember Newton's first law! If A were equat to V, you could not withstand riding in a plane, because of the tremendous forces on your body (smooth ride= constant velocity/ no relative motion.)

"Did the ball not come to a complete 0-MPH stop before reversing itself on it's new path. Please explain the instantaneous gain of
momentum with a complete reversal. (Transfer of inertia?)

You'd think so, wouldn't ya?

That's where elasticity comes into play. If there was no elasticity, the change is instantaneous resutling in "infinite" force due to t becoming zero (and the colliding objects would shatter.) In our case, it takes about a millisecond or two.

Slide rule? I'm not old enough to remember those things (I've seen them in "geek museums" though...