So many fundamental physics problems involve rigid body rotation that mastery of the subject is essential to many science and engineering undergraduate degrees. Rigid body rotation is typically taught in introductory mechanics courses and while students are generally comfortable with the corresponding kinematic equations, torques and moments of inertia are more difficult to conceptualize. This paper discusses a teaching approach we have developed that exploits the Falling Rod Race, in which the angular acceleration of rods with different weights attached are compared. We present the underlying theory for two different classes of weighted rods using torque, describe an adaptable classroom demonstration that highlights the essential physics, and produce a plug-and-play numerical code for instructor and student use.

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Supplementary Material

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