We describe the features and reasons for occurrence of the peculiar oscillations in the speed and acceleration of a taut chain passing over a rotating sprocket. With an increase in the number of teeth, these oscillations are smoothed out and disappear in the limiting case of a flat belt drive.

Uniform and uniformly accelerated motions are the basic types of mechanical phenomena and are studied in detail in physics courses. The only example of variable-acceleration motion amenable to a simple mathematical description and presented to introductory physics students worldwide is the example of harmonic oscillations. In this paper, we consider the simple instructive case of the jerky motion of a chain passing over a sprocket wheel.

A sprocket is a profiled wheel with teeth that mesh with a chain, track, or other perforated or indented material. Sprockets are used in bicycles, motorcycles, tracked vehicles, and other machinery to transmit rotary...

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