Disk with a Hole Rolling in a Semicircular Well
Disk with a Hole Rolling in a Semicircular Well
The center of mass of a disk with a hole is offset from the disk's geometric center, so that as the disk rolls in a circular well its motion is irregular.
This Demonstration simulates the motion of a disk of radius with a hole of radius at a distance from the center. Lagrangian mechanics are used to get the equation of motion for the animation and to compute the traces of the center of mass and the geometric centers of the disk and the hole.
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