Lemos - arxiv.org 2008

Failure of intuition in elementary rigid body dynamics
Date: Thu, 10 Jan 2008 17:52:39 GMT

Nivaldo A. Lemos
Four pages; to appear in European Journal of Physics

Suppose a projectile collides perpendicularly with a stationary rigid rod on a smooth horizontal table. We show that, contrary to what one naturally expects, it is not always the case that the rod acquires maximum angular velocity when struck at an extremity. The treatment is intended for first year university students of Physics or Engineering, and could form the basis of a tutorial discussion of conservation laws in rigid body dynamics.

Note that this paper isn't really a research paper. But, it addresses an issue that Paula Heron talked about at the summer Foundations and Frontiers of Physics Education Research meeting, a piece of ongoing work at the University of Washington. So, going on that thread, it seemed relevant to post it here. - MCW.