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Re: Capacitor charge, were is it?



Tesla List wrote:
> 
> >From sroys-at-umabnet.ab.umd.eduThu Oct 31 22:15:52 1996
> Date: Thu, 31 Oct 1996 09:20:42 -0500 (EST)
> From: Steve Roys <sroys-at-umabnet.ab.umd.edu>
> To: tesla-at-pupman-dot-com
> Subject: Re: Capacitor charge, were is it?
> 
> On Wed, 30 Oct 1996, Tesla List wrote:
> 
> > Take the electroscope and approach with a CHARGED DIELECTRIC
> > ROD and the leaves separate as above.  Now with the rod still held
> > near the ball, touch the ball only with your other hand or a ground wire.
> >  The leaves collapse.  Remove the wire or your hand from the ball.  They
> > stay collapsed.  Slowly pull the charged rod away and the air surrounding
> > the ball becomes charged to the opposite polarity and the leaves
> > magically open up again with no rod there.  The charge is in the air and
> > not the metal or leaves.
> 
> I've not tried this (no electroscope), but I've seen the "classical"
> explanation.  Starting with a closed, electrically neutral system
> (electroscope), moving the rod closer to the ball attracts charge of the
> opposite sign, redistributing the charge so that the system still has no
> net charge, but is electrically polarized. Your hand (or ground wire)
> takes off some of the charges that are hanging around at the ball. When
> you move everything away, the charge redistributes itself. Since you've
> removed a particular polarity of charge with your finger, the system is no
> longer neutral, but has a net charge, thus the leaves pop apart.
> 
> 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