Physics Q (x post)

[Magic_Man]

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This doesn't have anything to do with magnetostatics as far as I can tell. This is an effect of gravity. The spinning magnets tilt towards earths gravity (down) and put more friction between the surface there, meaning more force on the bottom half of each part of the rotation at the glass/magnet interface, causing it to move right when spun clockwise and left when spun counterclockwise. Just like a wheel.

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I was starting to think my solution was way too simple to be correct, but I believe this is the correct answer.

As the magnet starts to fall towards the earth due to decreased friction, there begins an inbalance in the friction between the lower and upper contact points of the spinning metal upon the glass. The lower part of the glass becomes an area of increased friction due to both the shape of the magnet and the fact that the friction created by the magnet moving downwards affects the bottom part of the spinning metal most. Thus when the magnet is spinning clockwise, the metal at the bottom spinning to the left in a U shape manner pushes the magnets right, just like a wheel would.

This is correct, no?

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Easy enough to test. OP, can you spin them on a horizontal plane and let us know if they still move in predictable directions?