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Re: Capacitor Charge-Were is it?

Tesla List wrote:
> 
> >From huffman-at-fnal.govTue Oct 29 22:47:16 1996
> Date: Tue, 29 Oct 1996 11:03:10 -0600
> From: huffman <huffman-at-fnal.gov>
> To: List Tesla <tesla-at-pupman-dot-com>
> Subject: Capacitor Charge-Were is it?
> 
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> 
> Hi All,
> I want to thank everyone for the replies. For me this has been a very
> interesting discussion although I still am having problems with it. It
> seems like the chicken and the egg question to me. You can't have a
> capacitor without a conductive plate/s and a dielectric. If I say the
> charge is on the plates, I probably should say the charge is on the surface
> of the plate/s, since that would put it in the dielectric. If you dump
> charge on the inside of a conductor it moves to the surface, and I
> understand the charge cannot be in the metal plate. I still envision all
> those electrons crowding around on the metal plate of a capacitor.
> Dielectrics are strong, dielectrics are impressive, but it's conductors
> that do all the work. (sorry Mr. Clemens)
> 
> In a realm we cannot see, can we really know?
> Sockit to me, just don't kick me off the list.
> Dave Huffman
> 
> P.S. The two capacitor problem...
> The lost energy goes into making heat, light, EM radiation, sound, etc. Why
> 1/2?
> I know it's not the same situation, but does half the energy also get lost
> going from the Cp to Cs?
> Can I transfer energy from one cap to another with minimal loss?


Dave,

The best energy transfer occurs with matched impedances.  This is in the 
case of the equal cap vlaues stated in the problem.  The loss shown here 
is a rare one in electronics applications as we are rarely charging one 
cap, removing the supply, and discharging into another purely capacitive 
load.  Just look at this as a special case.  It won't really impact 
anything but Tesla coils which are capacitive discharge systems with 
resonant inductive linkages for voltage rise and an output capacitor to 
feed the voltage out into the air.

In one of your earlier paragraphs above you noted that you can't have a 
capacitor with metal plates and you are right, but a capacitor is a 
circuit component designed specifically for electrodynamic systems with 
metallic circuits only!!  It is a very special case item dealing with 
charges.  The dielecric is quite happy and will retain charges virtually 
forever without old mr. metal ever approaching.  The charge can be made 
to do electrostatic work without metal only via coulomb forces outside of 
metallic circuits.

Richard Hull, TCBOR