Translational and Rotational Kinetic Energies of a Motorcycle

This Demonstration shows how the total kinetic energy is divided between translational and rotational contributions according to the equation

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You can choose two different trajectories with the "trajectory" button: parabolic with and another one similar to a chicane, a serpentine curve, with .

The right plot is a model for a motorcycle on a circuit where the red point represents its barycenter. The motorcycle always moves tangent to the trajectory, and the length of the green bar is proportional to the angular momentum; in the real case it is the sum of several contributions (engine, gear, etc.).

The left plot shows the repartition between the two energy contributions for every moment that is related to the curvature radius. You can toggle its display in the right plot with the "show/hide curvature radius" checkbox.