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Re: Capacitor charge, were is it?



Tesla List wrote:
> 
> >From lod-at-pacbell-dot-netWed Oct 30 21:30:30 1996
> Date: Sun, 29 Oct 1995 23:18:12 +0000
> From: GE Leyh <lod-at-pacbell-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: Re: Capacitor charge, were is it?
> 
> Richard Hull wrote:
> 
> <snip>
> 
> > The idea that there are actually a quantity of electrons stuffed on a
> > metal plate is pretty stupid and somewhat niave.
> 
> How would you then explain the operation of a classic electrometer, where
> two gold leaves suspended in a vacuum repel each other, when a charge is
> deposited upon them?
> I think that the main point of contention in this argument is simply the
> definition of the word 'charge'.  For the sake of discussion, I would like
> to suggest the classical definition, where charge is measured in coulombs
> and the charge on a electron is 1.6 e-19 coulombs.
> Energy (or work) is measured in Joules, which has units of volts X coulombs.
> 
> > Have you ever brought
> > the back of your arm up to a slab of metal WITH NO POWER SOURCE
> > ATTACHED and felt the hairs stand on end? ( I THINK NOT!)  What about a
> > piece of teflon or styrofoam?  (ALL THE TIME)
> > Where is the REAL charge retained?  (the dielectric).
> 
> Actually, a dielectric need not possess a net charge in order to store
> electrical energy.  Energy (not charge) is stored in a dielectric by
> distorting the orbits of electrons around atoms (like cocking a spring),
> thereby producing an electric field. It is the electric field that moves
> charge around on nearby conductors (or arms).  If the number of electrons
> and protons in the dielectric are equal then it has no net charge, regardless
> of how much stored electrical energy it might contain.
> 
> -GL

All,
	I brought up the point of the electrometer that Benjamin
Franklin used as a simple example of a device that contains no
dielectric. There are also simple instance were a charge can be
placed on normally nonconductive substances (i.e.: a rubber mat).
But this all roots itself back to a fundamental law of physics
we should all remember. Electron flow (i.e.: the bucket effect),
resides on the surface of an object. For example a wire containing
multple conductors will have less resistance than a solid conductor
will have. The reasons for this result are simple, more surface 
area. This is also the same for capacitor construction. More surface
area to collect the charge and less distance between the plates
tends to increase the potential. 

	In the reverse, more dielectric does not mean more charge
and more metal in the plates does not mean more charge. The key
here is surface effect. 

What does this mean? Well the charge is not in the dielectric! And
the charge is not in the plates either! Its on the surfaces of these
two different materials.

Enough!
D. Gowin