Posted by: Dale () on Fri Dec 3 07:38:49 2004

Hi Again Dale.
>
> It is understandable that the members of Paul’s site would have problems with my swing model if they believe torque is not a factor in generating bat speed. I would appreciate it if you would ask them their opinion on the following question.
>
> The right hand is held at a fixed position while a bat is cocked away from a heavy bag about 90 degrees by the lead-shoulder counter-rotating the lead-arm and bottom-hand forward. While keeping the right hand in a fairly fixed position, the bat is then accelerated to contact by the rotation of the lead-shoulder.
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> Do they believe torque was not a factor in accelerating the bat to contact?
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> I would appreciate their thoughts,
>
> Jack Mankin
>
OK Jack, here is their response:

"Sometimes I really don't know where Jack is coming from other then he appears to be confused about the nature of work and momentum. Of course there is torque involved. The torque being generated by rotating the torso (shoulders). This has been my position from day one. Most everything else is reactive to the rotation of the torso/shoulders. You cannot instantaneously moved a mass from zero to maximum speed without applying an infinite amount of force. Same thing is true with rotation. You cannot rotate something from a rest position to maximum angular velocity unless you apply infinite torque. In this case the infinite torque is being applied by the rotation of the torso and everything else is holding on for dear life as it accelerates up to rotational speed. This whole concept of active torque of the hands is a can of worms. As demonstrated by the simulations, the reactive torques a changing rapidly and it is virtually impossible for the human body to make adjustments other than just letting " it happen" as in rotate like hell and hold on for dear life and then apply some fishhook at the end."