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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