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among the explanations for the Coriolis force I've seen is a mention of the ice skater's rotational acceleration by pulling arms in radially.

I've always understood the spinning ice skater as conservation of angular momentum. However, I do see that the Coriolis force cross product formulation of -2m omega x v vector (cross product of rotational velocity and the velocity of pulling the arm in ) yields a vector that is tangential to the arm's spiral sweep and should cause rotational acceleration.

Can someone confirm that the rotating ice skater system is a satisfactory example of this. I've already read through an analysis of forces in the inertial frame that is posted at Why does a ballerina speed up when she pulls in her arms?

which seems pretty thorough but doesn't mention Coriolis so I'm not sure that my perspective is correct.

Thanks,

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    $\begingroup$ My view of this is that the author of the excellent answer you linked concentrated on a very full account of the conservation of angular momentum, that he simply didn't think of the viewpoint from a reference frame that incorporated the Coriolis Force. I would think, obviously enough I suppose, if you could "map" every aspect of the ice skater to a standard CF example, you could confirm/ refute it. My point is that just because the author didn't mention it probably has no significance. $\endgroup$ – user108787 Nov 3 '16 at 0:09
  • $\begingroup$ Right. Angular momentum is conserved. The term "coriolis force" is just the name for the force she feels making her speed up.. $\endgroup$ – Mike Dunlavey Nov 3 '16 at 0:14
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The Coriolis force is always directed perpendicular to the movement of a body. So, it doesn't exert any influence on the speed and kinetic energy of the ice skater (in fact, it could only change his direction). In other words, it does no work in this situation.

On the other hand, the force one has to apply a force inward to counter the centrifugal force does do a mechanical work: this is the work the ice skater has to do by his muscles in order to keep spinning (that is, the increase in rotation is a result of him pulling in his arms).

Any of this is in contradiction with the answer you referred to. The author of that answer didn't considered a non-inertial frame in his explanation, that's all.

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When the rotating skater pulls his arm in close to the body, his moment of inertia $I$ decreases. As the angular momentum $L=I\omega$, where $\omega$ is the angular velocity, is conserved, this means that the angular velocity $\omega$ has to increase so that $L$ stays the same. This has nothing to do with the Coriolis force.

Note: The Coriolis force is an apparent force that like the centrifugal force only appears in a rotational frame of reference. The Coriolis force is not seen in an inertial frame of an observer.

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