Races between moving objects are an engaging way to teach dynamics to introductory physics students. One standard example consists in racing hollow and solid cylinders as they roll down an inclined plane. Another striking demonstration is a race between two marbles on side-by-side tracks that start and end together, but with one track taking a straight path and with the other following a cycloidal shape. In the present article, two objects (having the same mass and shape) are launched from the same starting height with the same speed up an inclined plane. One of the objects is subject to kinetic friction. The other object is not because it rolls without slipping on wheels along the incline with negligible rolling friction. Each object travels upward, slows down, and then turns around and retraces its path to its starting point. If the two objects are launched simultaneously, which one makes it back first?
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PAPERS| April 01 2021
Carl E. Mungan; A Race Between Rolling and Sliding Up and Down an Incline. Phys. Teach. 1 April 2021; 59 (4): 247–249. https://doi.org/10.1119/10.0004147
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