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How many joules --> e.m. waves



On 16 Apr 1997 12:20:06 Bob Sciamanda was correct in writing:

I'll go out on a limb and predict that if you do the integration carefully,
ALL of the capacitor's original energy will go into Ohmic heating. The
differential equation whose integral you are using I(t) does not know of
any radiation mechanism; it states Kirchoff's loop law which says energy
is totally accounted for by the terms in the equation. You would have to
include a term which sinks energy by way of some "radiation resistance".
Math is not magic; neither is it a source of new physical information; it
is logic, and its conclusions will only make explicit what is already
implicitly in the premises which it was handed.

I just discovered this the hard way; no matter how small R is the value
of H is always 50 joules. Thus my approach, based on the assumption that
the differential equation for the LCR cirquit discribes the i(t) correctly,
was wrong. The problem posted yesterday remains unsolved. I do not know how
to calculate the radiation resistance. And I hope to learn this from a more
knowledgeable phyl-L-er.
Ludwik Kowalski