"Wimpie" wrote in message
...
The reason that you don't need to take magnetic dipole radiation into
account in real mechanical systems is because of the radiated power is
very low (low RPM in practical mechanical systems). Friction
(bearings/air, eddy current, etc) is orders of magnitude more then the
"friction" caused by the EM radiation.

Further proof, if any were needed, that a short antenna is a poor radiator.

(Frequencies of mechanical rotation representing wavelengthe of several
miles, against which the length of the magnet is trivial, and why, in the
case
of the superconductor example, there is no measurable decrease in
rotational speed, in the short term, at least.)