Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Dec 8 14:37:50 2009

>>> Jack -

What do you think of this info:

http://www.physics.usyd.edu.au/~cross/baseball.html

see section 4 on swinging the bat

and linked paper:

http://www.physics.usyd.edu.au/~cross/PUBLICATIONS/44.BatSwing.pdf <<<


Hi Tom

Thank you for providing links to the info. It would have saved both of us a lot of grief if papers of this nature had been published much earlier. I think I can safely say that I was among the first, if not the first, to write about the significance torque applied at the handle had on the angular displacement rate of the bat. In fact, it was Professor Adair's book, "The Physics of Baseball," that prompted me to write my first paper on this topic.

An article in your link states, "Adair provides a few answers in his book "The Physics of Baseball" but he does not give the directions or the torques." -- The reason he did not address the torques is because he had concluded that the direction of force applied by the hands was not a factor in generating the bat's angular acceleration -- in his book, he states, "Forces applied at the handle have negligible impact on ball flight."

Findings from my study concluded that the hands applying force from opposing directions (torque) was a major factor in generating bat speed. In the early 1990s, I sent Professor Adair a 25-page report of my findings. My paper also addressed our differences on the power source of the swing. He maintained that it was the kinetic energy developed from the body's linear progression that provided the energy. My study concluded that the energy was derived from the rotation of the body about a stationary axis. -- Below is a post from the archives that expands on that controversy.

Re: Torque

When I first presented the principles of my Rotational Swing Model (CHP, THT & BHT) on the Discussion Board in 1999, the reception was highly negative. In fact, I seldom perceived a friendly tone in a post. Tom, I would like to thank you for being one of my very few early supporters. I know you received a lot of grief for that support.

Jack Mankin