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Re: Capacitor charge, were is it?
On 10/27/96 22:25:02 you wrote:
>
>>From jim.fosse-at-bdt-dot-comSun Oct 27 21:44:50 1996
>Date: Sun, 27 Oct 1996 16:37:18 GMT
>From: Jim Fosse <jim.fosse-at-bdt-dot-com>
>To: tesla-at-pupman-dot-com
>Subject: Re: Capacitor charge, were is it?
>
>
>[snip to save Chip's eyes]
>>>If this is true we could not have a capacitor with a charge that has no
>>>dielectric (vacuum).
>>
>>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.
>>
>[ditto]
> Sorry,
> But a vacuum is NOT a conductor. The conduction in a
>vacuum tube is due to the electrons boiled off the cathode flowing
>through free space toward the positive plate. If you reverse the
>applied voltage (plate more negative) then no current will flow. This
>is exactly how a vacuum rectifier tube works. If the vacuum were
>conducting, then the vacuum rectifier would conduct in both
>directions.
The vacuum diode conducts in one direction only because the plate is charged
positively and the electrons are charged negatively. If the vacuum were not
a conductor, no electrons would flow in either direction. Make sense?
Phil
>In other devices, without a thermonic cathode, the electrons are
>ejected/ripped out of the cathode whenever the electric field is
>greater than the work function of the material. That is: when the
>force on the electron from the electric field is greater than the
>force holding it in the material. This effect is called field
>emission.
>
> Regards,
>
> jim
Phil Gantt (pgantt-at-ix-dot-netcom-dot-com)
http://www-dot-netcom-dot-com/~pgantt/intro.html