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Re: Capacitor charge, were is it?
In a message dated 96-10-27 04:42:21 EST, you write:
<< Since a vacuum is a conductor (i.e vacuum tube), you cannot have a
potential
difference (charge) in a pure vacuum. This concept is theoretical.
>>
How then does the 1000pf Glass cylinder "vacuum" cap store its charge? Not
likely in the glass since the plates are at right angles to the cylinder
wall. The answer perhaps is that the charge is stored neither *in* the
plates nor solely in the dielectric but rather in the field surrounding the
plates. This field is influenced by the dielectric (if any) between the
plates.
It also seems to me that *electrostatic* fields (charges?) can exist in a
vacuum with out current flow, but I agree that the tube analogy is troubling.
It is, however, well known that tubes suffer from "interelectrode plate-grid
capacitance." If plates in a vacuum could not hold a charge, interelectrode
capacitance would not be a problem in tube circuit design - but it is.
Additional thinking needs to be done on this subject I suspect :)
-DavidF-