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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