What happens to the angular momentum?

AI Thread Summary
Angular momentum is conserved in a closed system, and when an ice skater or spinning top stops, the angular momentum is transferred to the surrounding environment, primarily through frictional forces. As the skater extends their arms, they slow down due to the conservation of angular momentum, and when they pull their arms in, their angular velocity increases. When the skater eventually stops spinning, the angular momentum dissipates into the Earth, which has a negligible effect due to its massive size. This understanding clarifies that angular momentum is not lost but rather redistributed. The discussion highlights the importance of recognizing how angular momentum behaves in relation to external forces and systems.
valleysheep
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Hi,

Apologies in advance if this is in the wrong section or if i have violated a particular rule. (First post).

I don't have a great grasp of classical mechanics, and so some of the simple aspects are lost to me :P. So to the question.


Taking an ice skater as an example (or any other spinning object), when the skater throws out his/her arms they will slow down and when they pull them in their angular velocity increases, as to conserve angular momentum. However, i was wondering what happens to the angular momentum when the skater stops spinning. (Or when a spinning top is at a stand still).

I believed that frictional torque slows the object down (this is where my understanding of CM is lost). Angular momentum must always be conserved and so where does it go to when v=0.


Thanks for any help :P.
(Is it because angular momentum is only conserved in a closed system ?)
 
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It goes into the Earth, but the Earth doesn't care-- it has way more already.
 
Oh wow, makes sense now XD. Feel like a fool now for missing something so obvious :P.

Thank you for helping.
 
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