Why is Euler’s disk significant?


I’ve seen videos of the disk moving but I don’t understand why it stops abruptly and what we can learn by observing it

In: 7

What the cow is that?

The Euler’s disk (pronounced *oilers*) demonstrates a kind of circular rolling and rotating oscillation that increases in frequency as the disk descends until it abruptly stop as a certain frequency.

This motion is a useful and simple example with which to explain how to break down a seemingly complex motion into its fundamental forces and velocities.

Gyroscopic precession from its rotation keeps the disk from falling immediately.

Rolling friction between its edge and surface consumes energy, so the disk gradually descends. As it descends, the disk’s rotation slows, but its oscillation speeds up, until (theoretically) its frequency nearly matches that of one of the disk’s harmonic modes.

Harmonic deformaton of the edge interferes with its oscillating motion causing the entire edge to briefly lose contact with the surface. The motion’s geometry collapses, and the disk finally falls.