harp AP 2010
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Homework Statement
If an acrobat isn't touching the ground how can he changes his rotation speed?
Changing Rotation Speed of an Acrobat Not on the Ground
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If an acrobat isn't touching the ground how can he changes his rotation speed?
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harp AP 2010
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hi tiny-tim ;)
he can move his arms and legs, causing a change in his MoI and therefore his rotation speed?
he can move his arms and legs, causing a change in his MoI and therefore his rotation speed?
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hi harp AP 2010! 
exactly!
if he moves his arms or legs in or out, or even if he bends at the waist, his https://www.physicsforums.com/library.php?do=view_item&itemid=31" will stay the same …
if he was originally rotating along a principal axis (so his angular velocity is in the same direction as his angular momentum), his rotation direction will stay the same, but the speed will change;
if he wasn't originally rotating along a principal axis, his rotation direction will precess also
exactly!
if he moves his arms or legs in or out, or even if he bends at the waist, his https://www.physicsforums.com/library.php?do=view_item&itemid=31" will stay the same …
if he was originally rotating along a principal axis (so his angular velocity is in the same direction as his angular momentum), his rotation direction will stay the same, but the speed will change;
if he wasn't originally rotating along a principal axis, his rotation direction will precess also
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