In the spirit of the holidays.

Let's assume that a dreidel is spinning counter-clockwise at frequency $f$ on a table.

From external point of view, what will I see if I rotate the table clockwise at the same frequency, assuming that both the dreidel and the table are spinning with the same center of rotation?

Is it possible that an external observer will see the dreidel freeze? Is it possible for an external observer to see the dreidel at all?

Any help is appreciated.


The table affects the rotation of the dreidel in two ways: it supports the dreidel by the normal force and it slows the dreidel down due to the friction.

If the table rotates in the opposite direction, the normal force won't change, but the friction will slightly increase, which will cause the dreidel to slow down more and stop sooner.

The visual impression of an external observer will depend on the surface of the table. If it is uniformly colored, the observer will not notice much difference. If it has a pattern, revealing the rotation of the table, the observer may get an impression that the dreidel is spinning faster than it really is.

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