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Re: Capacitor charge, were is it?
Edward V. Phillips wrote:
> Re: Charges in vacuum
> Electric charges can indeed exist in a vacuum. Very
> common for the walls of evacuated tubes to accumulate charges
> which can deflect electron beams, etc. Screens for CRT's have
> to be manufactured with consideration of buildup of charge
> which can deflect the electron beam away from the screen.
> Ed Phillips
In this example, the charges reside on the surface of the glass
wall, not in a vacuum. Stray electrons from the beam collide with
the glass and deposit these charges.
When I stated that charges cannot exist in a vacuum, I am defining
a vacuum as a volume of space that contains _no_ mass. I believe
that this is the classical definition.
Both the glass wall and the electrons in the beam have mass, and so
do not count. The space between free electrons in the interior of
the CRT counts as vacuum, but that space contains only the electric
field lines between electrons, not the charge itself.
The point that I am trying to make is twofold:
1) All electric field lines terminate in a charge, and a charge only.
2) No one has ever measured an electric field line terminating into
empty space. All measured field lines terminate into either a
positron or an electron.
-GL