Let me elaborate... at any given instance Gravity is actin on the mass of the golfer and some combination of the golfers muscles are contracting. If we were to take a snapshot in time and add up all of those forces vectorially it would have a manitude and direction. That force must be reacted or our body will accelerate (move) and its reacted by shear and normal forces at our feet. The shear and normal forces at our feet are "equal" but "opposite" (direction) to our muscle forces and gravity. That direction is not directed (necesarily) through the axis or center of rotation so its not a "central" force.
At issue is verbage. Conservation by definition implies: "limited supply" . When are muscles and gravity are applying forces which create momments we are increaing (or decrease) alpha or angular acceleration and conservation does not apply. Only if those forces are directed through the axis of rotation and therefore cannot create a torque are they central forces. I'm saying COAM does not apply. I'm not saying as mass gets redistributed the system won't speed up or slow down... The only way to know whats happening is by solving the equations of motion at each instant in time.
Last edited by no_mind_golfer : 10-27-2008 at 02:30 PM.
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