3A40.25 - Ball on a Track vs. Pendulum
Align the track and the pendulum so the ball and the pendulum have the same equilibrium position. Start them oscillating from the same position. Note that the pendulum and ball travel the same arc, have the same mathematical form, but that the ball on the track has a lower frequency.
- Laurence A. Marschall, "Driven 'Portulum': A Rolling Ball as a Simple Oscillating System", AJP, Vol. 49, #6, June 1981, p. 557.
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