606 Spinning

The rotational speed of the disc is going to be increased gradually. Which nuts will skit first, the outer ones or the inner ones?

The F=mv2/r should not be used to compare the required centripetal force for this scenario since nuts inner nuts have different tangential speed from outer nuts.

In such scenarios (spinning mixers, merry-go-rounds, lazy susans) where all the objects have the same angular velocity ω, F=mrω2 is the better formula to use. At the same ω, the outer nuts doing circular motion with a larger r require a larger centripetal force compared to the inner nuts. Outer nuts skid first.

In fact, if one is situated right at the middle, no centripetal force is required at all. This explains why the bean at the middle had the last laugh.

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