The High Road/Low Road race is often used as a qualitative prediction activity. A marble is released simultaneously on two elevated tracks that differ only in the middle section where the Low Road dips before finishing at the same height as the High Road. Typically a minority of students correctly predict that the Low Road will finish first. In this investigation an energy and segmented constant acceleration-based Desmos model is developed to predict the time required to traverse each track. The effect of rotational inertia on the model is also explored. Those predictions are then compared with the time measured by photogates and video analysis.

Topics
Gravitational energy, Energy conservation, Rotational dynamics, Educational aids
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Supplementary files and Desmos simulations by
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© 2019 American Association of Physics Teachers.
2019
American Association of Physics Teachers
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