Re: Where does the other 13% of heat in induction heating come from?

Carol,

I haven't got a clue how to interpret this question.  Off the top of my
head, I can think of induction heating processes (such as in a transformer)
where 100% of the heating comes from the eddy currents, and I can think of
processes (such as using a magnetic brake to stop a wheel) where the
percentage of heating coming from eddy currents can be much smaller.  I'm
afraid that I would need to know more before being able to provide a
meaningful answer.

To illustrate what I mean, consider the simple (?) idea of using a magnetic
"brake" to slow the rotation of a metal wheel.  The effectiveness of this
magnetic brake (meaning: the rate of dissapative heating by eddy currents)
will be strongly affected by the resistivity of the metal, and the geometry
of the wheel and magnet.  There may be other brakes acting on the wheel,
which may produce frictional heating.  And, don't forget that the bearings
on the axle will also have some frictional dissapation, that a rapidly
rotating wheel in air will be slightly heated by the viscosity of the air,
and that a driven wheel will have some frictional losses associated with
the driving mechanism.  And so on -- there are lots of ways for friction to
enter the problem, and thus contribute to heating the wheel.

So the short answer is, even for something as straightforward (?) as a
magnetic brake on a wheel, a 13%/87% split would come from all the details
of the problem, which you didn't give.  So I'm not sure how to answer. 
But, you could look at your reference and try to puzzle out what the other
sources of energy dissapation might be.  Basically, you'd be looking for
ANYTHING that would contribute to turning about 1/8 of the initial kinetic
energy (or whatever) into heat energy.  And, trust me, nature has provided
lots and lots of ways for dissapation to enter the picture, especially at
the level of a 10%-ish loss.

Good luck!  I hope that this will give you a good starting point.

Aaron J Redd