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Re: Capacitor charge, were is it?

>Message-ID: <199611020526.WAA07030-at-poodle.pupman-dot-com>
>Date: Fri, 1 Nov 1996 22:26:19 -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?

>From hullr-at-whitlock-dot-comFri Nov  1 21:50:44 1996
>Date: Fri, 01 Nov 1996 11:53:10 -0800
>From: Richard Hull <hullr-at-whitlock-dot-com>

>> 
>> I would think that if the charge were in the air, you could blow the air
>> away, or simply move the electroscope, and the leaves would collapse.  Is
>> this the case?
>> 
>> Steve Roys
>
>
>Good boy Steve!!!
>
>It is always the space that is charged, but the molecules in the air 
>contribute to the alteration of same.  You would have to blow away the 
>air inside the jar of the electroscope as well as outside.  Remember, the 
>charge is separated at each end of the air/metal rod interface.  To prove 
>this, and mix the air, just simply lift the stopper, rod, leaves, and all 
>out of the bottle.  The leaves will collapse!!
>
>Richard Hull, TCBOR


   Are you telling us that mixing the *internal* air in air-dielectric
   capacitor discharges it?  Then how do our pocket dosimeters work? 
   This just cannot be true.  They are little chambers with an
   extremely dry gas inside them.  We charge our pocket dosimeters up
   to about 300 volts and they can stay charged forever unless exposed
   to ionizing radiation which produced ion-pairs in the gas.  The
   internal gas can be circulated by any and all motions of the
   dosimeter.  The dosimeter is exactly the same as the gold-leaf
   electroscope only we have a fiber instead of a leaf, and the
   dosimeter is optically read by the user.  If the charge really were
   on the gas then mixing it would discharge the capacitor.  But by
   years of experience it doesn't work that way as far as I can see.

   Has anyone ever put in a fan inside a sealed electroscope?  That
   would be interesting!

   I've always considered the electrons to be at the interface of the
   conductor and the metal.  Charged metal conductors have no electric
   field inside them (otherwise there would be a continual current). 
   But that doesn't say the electrons cannot be very close by.  Nor
   does it mean the thay have to leave the vicinity.  They don't travel
   into the insulator (they cannot) but they do distort the internal
   electric field in the insulator.  With solid insulators where it is
   actually possible to separate the conductor from the insulator, the
   electrons of course want to stay where the field traps them - on
   the insulator. But with gasses it's sort of hard to do that.

   But inside the electroscope in order for things to repel each other
   (the gold leaves), the charge must actually exist there and not 
   mixed in to the air in the bottle.  If the electrons were on the
   gas then the gas would repel itself.  This isn't what's hapenning. 
   In order for the force to be felt by the gold, The electrons sit on
   the very surface of the gold but not *in* the gold.

   Your inletting air to the electroscope isn't really a fair test
   since the air you let in contains all sorts of ions of both
   charges!  I think that if you let in pure air with NO ions and no
   water vapour this wouldn't happen.  Anybody done this?  Letting in
   mixed ions will discharge any isolated charged surface (either
   polarity). 

   Do you think Einstein's research (leading to his Nobel Prize),
   which involved the discharging of capacitors by ultraviolet light,
   might be pertinent here?

   Incidentally, what you say about mixing the air in an air capactior
   thereby discharging it might be true at higher voltages than 300 volts.

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