Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Apr 4 15:18:36 2000

>>>This question gets asked frequently. The answer is an emphatic NO, the body mass does not play a role if the ball is struck on the sweet spot. The distance can be easily calculated from conservation of momentum and simple ballistics equations. Suggested reading: "the physics of baseball" by Robert Adair. <<<

Hi Steve

I am 90% sure that what you are stating is true. I would be 100% if the angular displacement of the bat was solely derive from swinging the bat as if it were on the end of a rope as Mr. Adair claims. But test that I conducted shows that about 50% or more of bat speed is generated from torque. Torque requires forces “across” the linear axis of the bat, not “inline” as in swinging it with a rope.

So this presents me with a problem. --- Since the mass of the bat is a key factor in calculating the energy impacted to a ball from the conservation of momentum, what constitutes the true mass of the bat. Is it only the sweet spot area or is the handle included. Then what about what is attached to the handle. --- Suppose the bat were welded to a 200 lb. flywheel. Or suppose the batter choked-up to the trademark, would that have any effect on the value given to mass in our calculations.

Jack Mankin