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Re: Missing Energy



On Thu, 20 May 1999, James G. Pengra wrote:

where did the energy go?

Randy,
I think (it's been a while since I did this problem) that the energy
goes into I^2*R heating of the connecting wires.
If you discharge a single capacitor through a resistor, you can show
that all the stored energy goes into heating the resistor. However, in the
calculation, the resistance value is not a factor (it can't be if you think
about it). So, no matter how small the R value, you have the same
conclusion as to the energy transfer.
Connecting the two capacitors in your problem is just another version
of the same problem.

--Jim Pengra, Walla Walla, Washington 99362 mailto:pengra@whitman.edu


Or, if there is no resistance, I'm guessing the current will oscillate
back and forth and the energy will alternate between kinetic energy and
(electric) potential energy.

I think it is easy to forget that resistance is acting in circuits. It
reminds me of the question raised recently about why the electrons don't
accelerate to high speeds in the presence of the electric field within the
wire.

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