# Physics of Glove side movements in Baseball Pitching

I had a question that I think relates to conservation of angular momentum.
What are the physics behind a pitcher using his glove side in these gifs? Could it help accelerate his arm by pulling his glove side shoulder/arm in (or out of the rotational plane)? I guess also need to take into account converting forward momentum in addition to the rotational.

Like this skater using her arm to jump?

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I think you called it,

his ball arm extends to increase its tangential velocity on release

and his glove arm comes in to increase his rotational velocity (because of conservation of angular momentum)

you could kind of approximate by ignoring the height difference between hands and assigning some geometric shapes with known rotational inertia ot particles as parts of body and glove and ball, intresting problem If it wasn't my last chapter but this one I would quantify everything to the best of my ability for ya, but yes your getting the concept

EDIT; re-looking at pics, ignoring any difference in height wouldn't work cause the rotational planes pretty vertical, but some approximations would still totally make this problem doable with a good degree of accuracy. The forward movement would qualify as cm of system movement and could just be added to the tangential velocity upon release (but he doesn't release tangent to the circle its more of an arch so that might throw off some numbers)

EDIT 2 : maybe it is roughly tangent to a circle with his cm at the center, that would make sense, I'd have to know more about baseball or decide on some reasonable approximations based on optimizing tangential velocity to help ya further

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mcloven