Rightangle lever paradox
Abstract
We present the problem of relativistic torques with particular reference to the rightangle lever problem and outline a simple solution. The important elements of our solution are, first, a reexamination of the classical relation between torque and angular momentum and, second, the consequent realization that in relativistic analysis there exists a net internal torque which exactly cancels the net external torque experienced by an extended body in dynamic equilibrium. We find that the lever has constant angular momentum according to all Lorentz inertial reference systems and that this is consistent with the relativistic relationship between torque and angular momentum. Our solution is not restricted to relativity. It is valid for a wider class of theoretical frameworks.
 Publication:

American Journal of Physics
 Pub Date:
 July 1975
 DOI:
 10.1119/1.9761
 Bibcode:
 1975AmJPh..43..615N
 Keywords:

 03.30.+p;
 Special relativity