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Missing Energy

Hi Jack, Randy:

It seems pretty clear to me that when the capacitors are connect together, they are connected across a difference of potential. Charge will certainly flow through the connecting wire. Spark, or not, when charge flows through the connecting wire across a difference of potential there is energy lost in the form of heat (light/sound with a spark).

Enlighten me if I'm wrong.

Stu Leinoff
ACC


JACK L. URETSKY responded:
Randy,
My understanding is the "missing" energy goes into an inevitable
spark that occurrs when when the connection is made.
However, what if the connection is done in a vacuum? Perhaps I should
think about that.
Brian McInnes
----------
From: Randy Sloper <rsloper@SOUTHWESTERN.CC.OR.US>
To: PHYS-L@LISTS.NAU.EDU
Subject: Missing Energy
Date: Thu, 20 May 1999 8:51 AM


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?

Any help will be appreciated.

Thanks,
Randy