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PC1672 Advanced dynamics


On the Poinsot Construction*

When the polhode rolls on the herpolhode
invariably in the plane,
the forces tend to be free.

When the polhode slips on the herpolhode,
the forces are not mundane,
they're nonholonomic, you see!


David N. Williams

*Inspired by a footnote to a discussion of the free rotation of a rigid body about its center of mass in Goldstein's Classical Mechanics, "Hence the jabberwockian sounding statement: the polhode rolls without slipping on the herpolhode lying in the invariable plane."

Copyright © 1974, 1999 by David N. Williams (University of Michigan)

Textbook reference


Top: PC 1672 home page | Up: 4.8 Stability of free rotations |

Mike Birse
8th May 2000