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Re: Capacitor charge, were is it?

>Message-ID: <199611020526.WAA06948-at-poodle.pupman-dot-com>
>Date: Fri, 1 Nov 1996 22:26:04 -0700
>Subject: Re: Capacitor charge, were is it?

>Date: Fri, 1 Nov 1996 09:53:14 -0500 (EST)
>From: Steve Roys <sroys-at-umabnet.ab.umd.edu>
>To: tesla-at-pupman-dot-com
>Subject: Re: Capacitor charge, were is it?

  [snip]

>Conductors pass the electrons on easily between atoms, insulators hold
>onto their electrons and don't let them go as easily.  The better the
>insulator, the stronger the hold on the electrons. Vacuum has nothing to
>retard the electrons.  Once the electron breaks free, it's free to go,
>governed only by it's initial momentum and the surrounding electric and
>magnetic fields.
>
>So in a sense, it seems like once an electron breaks away from a conductor
>into the vacuum, a perfect vacuum could actually be considered a perfect 
>conductor.

   ... you mean as is there isn't any loss to heating the vacuum?  OK. 

   But there is one property of a conductor that vacuum doesn't have:
   confinement of the charge.   When you talk about particles moving
   in a vacuum you're into the realm of particle accelerators.  Here
   we have a special problem of energy 'loss' with electrons or
   low-energy ions: space charge.  The energy isn't really lost it
   just goes into a useless form, the electrons repel each other and
   accelerate away from each other in random directions.  Think of the
   electron bundle as an expanding foam.   Theoretically this energy
   is recoverable.

   As Steve mentions, in a strong magnetic field the electrons lose
   energy to synchrotron radiation.

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