"Cecil Moore" wrote in message
om...
Roy Lewallen wrote:
That's been the downfall of many a perpetual motion proponent. A
permanent magnet produces both a field and a force. So it must be a
source of energy, right?

I would assume the *total* amount of energy in the magnet
is e=mc^2.

your term ONLY includes nuclear potential energy.

at ordinary energies, your expression is the correct approximation!

Gravity