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Re: Capacitor charge, were is it?

>Message-ID: <199611110525.WAA01768-at-poodle.pupman-dot-com>
>Date: Sun, 10 Nov 1996 22:25:37 -0700
>From: Tesla List <tesla-at-poodle.pupman-dot-com>
>To: Tesla-list-subscribers-at-poodle.pupman-dot-com
>Subject: Re: Capacitor charge, were is it?
>Reply-To: tesla-at-pupman-dot-com

>From ed-at-alumni.caltech.eduSun Nov 10 21:48:25 1996
>Date: Sun, 10 Nov 1996 19:27:19 -0800 (PST)
>From: "Edward V. Phillips" <ed-at-alumni.caltech.edu>
>To: tesla-at-pupman-dot-com
>Subject: Re: Capacitor charge, were is it?
>
>"Now what would happen if we cut that rod in two, put a very tiny
>   microammeter between the two half-rods and connected the leads of
>   the microammeter to the two half-rods such that the ammeter was now
>   in series with the rods, and then we turned on the field V.  We
>   agree that in the steady state there is no current flow in the rod.
>   But what would the meter read if we started with the field off and
>   the we turned it on?  Would the meter ever read any current?  Would
>   the current start and flow in one direction and stop, or would the
>   current turn around and flow back the other way?  Would there be
>   any net charge transferred through the microammeter if we left the
>   voltage on?"
>	At the time the field was applied there would be a 
>transient current through the microammeter, since the two
>ends of the rod to which it is connect are, in effect, small
>capacitors coupled to the two plates.  After the initial transient
>those two capacitors are charged, so a net current had to flow.
>	On turnoff the same thing will happen, with the direction
>of current flow reversed.
>	(Above assumes that that I read your statement right and
>this is not a trick question which fooled me!  I'm all pooed
>out tonight.
>Ed


  Ed,

   I think so too.  Now we already know what will happen to electrons
   in a vacuum with an electric field present, and we know that there
   is no ongoing flow of electrons from one half of the bar to the
   other.

   So my question is, where are the extra electrons on the half of the
   rod nearest to the V+ ?  They are still associated with/ attached
   to that half of the bar.  What is the nature of this bond?


 Fred W. Bach ,    Operations Group        | Internet: music-at-triumf.ca
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