quote:Now if you let your hands rotate in a circle, you basically swing a purse at the ball.
No, none of my hitters swing a purse... but yes, metal or wood... and i want them to swing the bat (or purse) circular... then physics can take over and you have effortless power because of the conservation of the angular momentum...
Objects (bats) executing motion around a point (spine/body) possess a quantity called angular momentum. For the simple case of a small mass (bat) executing uniform circular motion around a much larger mass [body] (so that we can neglect the effect of the center of mass) the amount of angular momentum takes a simple form.
The conservation of angular momentum demands that a decrease in the separation (distance of hands from spine)be accompanied by an increase in the velocity and vice versa. Meaning the further your hands are away from your spine, the slower the bat moves... the closer they are the faster it travels - this being physics all doing the work for you (with everything else being equal).
a bat following the hands in a circular motion covers no less area than a bat on a straight line... they both can cover entire plate they both can hit the ball whether it is an "inside" or "outside" pitch. They both can be in "hitting zone" for exact length of time....
no one can push/pull a bat around their body with more velocity than using angular momentum... just like no pitcher would ever push/pull a ball to home plate... they would use angular momentum as well to "conserve" energy to point of "release."
bottom line... hands to the ball has momentum but it is "ordinary momentum." It is a measure of an object's tendency to move at constant/decelerating speed along a straight path. Momentum depends on speed and mass. A train moving at 20 mph has more momentum than a bicyclist moving at the same speed.
For things moving in straight lines momentum is simply mass × speed.
Angular momentum measures an object's tendency to continue to spin. Angular momentum = mass × velocity × distance (from point object is spinning or around)
You plug in the numbers and let me know which is greater...
Linear Baseball Swing: Velocity is contant or slowing down (to the point of impact).
Rotaional Baseball Swing: Velocity is constant on increasing (to the point of impact).
But JMO.... and that of every Physics Professor in the world...