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Re: Missing Energy



Hi Randy-
You ask:
*******************************************************
I have recently posed the following question to my calculus based
physics class and am not sure I understand the results.

Given two capacitors C1 and C2 charged to potentials V1 and V2
respectively determine the energy stored in them.
Now connect the two capicitors together positive to positive and
determine the potential difference and energy stored in the capicitors.
If the energies are different, where did the energy go?

To my surprise, the energies are different and I am not sure where the
energy went. Did the changing flux of E-field create a B-field that
took away energy? Were photons emitted? How can the energy loss be
time independent? Am I way off?
*********************************
There are a lot of nice problems like this one in "Beyond
the Mechanical Universe" which is, unfortunately, out of print.
Like any good physics teacher, I will only suggest an answer.

Consider a closed system consisting only of the two charged
capacitors, separated from each other. How long do you have to wait
before they connect themselves in their new configuration?
Regards,
Jack

"I scored the next great triumph for science myself,
to wit, how the milk gets into the cow. Both of us
had marveled over that mystery a long time. We had
followed the cows around for years - that is, in the
daytime - but had never caught them drinking fluid of
that color."
Mark Twain, Extract from Eve's
Autobiography