Um. Actually I could
have sworn that this one had been answered a few years ago, but I can't find it. Oh well...
First of all, remember that to ask whether a magnet has
potential energy does not make much sense out of context. The potential energy
is in the system, not in the magnet as such. For instance, when a magnetic
object is in the attractive field of a magnet, there is a potential for it to "fall
towards" to be "attracted to" the magnet. The fall converts
energy that is stored in its situation. The converted energy could take the
form of heat, noise, air motion or the like. The energy released in the process
is exactly equal to the energy intrinsic to the separation between the magnet
and the object. That energy intrinsic to
the separation we call potential energy. We get a similar, closely analogous, example of potential energy when we
hold a body above the surface of the Earth. If the body bounces or it swings
like a pendulum, the energy keeps getting converted between potential energy
and kinetic energy (energy of motion) and back again, as the mass moves up and
down.
The further a falling body has to go, the greater the potential
energy that could be released in the fall. In your job you might be aware of
what happens to anyone who converts the potential energy of his height in a
tall building into kinetic energy by stepping out at the wrong floor. Or how
much of your own metabolic energy you must convert into potential energy by
climbing up the stairs to visit the spot from which the victim had fallen. What made a very dramatic mess of a patient
could be the energy equivalent of the catabolism of quite a small bar of
chocolate. Or a hefty tot of something sociable.
Cheers!
Jon
