Joe Hiddink had written;
"Now when this sphere sits on the ground, and the 1-terminal part of the
capacitor inside it is "on" the sphere becomes e.g. positive, and that
positive charge (or at least part of it) goes to the "ground." which
tries to absorb the charge and dissipate it.
But the next pulses, that are also positive make that earth (comb) feel
uncomfortable, it cannot absorb these same type of charges, it gets
annoyed with that darn piece of paper (sphere) and repels it. "
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You wrote;
> If I understand Joe correctly: A spherical capacitor is charged
> by applying a voltage, say positive, to the inside spherical
> plate. This in turn induces a negative charge on the outside
> spherical plate.
yep, thats the way I read it..
> The induced charge on the outer sphere results in an electric
> field between the outer sphere and a now induced positive
> charged ground.
> The inner spherical plate is then discharged, which induces a
> magnified positive (opposite) charge on the outer sphere.
> The outer sphere, by virtue of its rapid change in charge,
> now repels against the 'pre-induced' ground electrons (positive
> against positive).
> The cycle is repeated and results in a succession of force
> pulse reactions on the spherical capacitor structure.
> Is this close to what Joe is talking about?
Yes, it does appear that he is pumping the earth with positive
discharges that eventually saturate the area under the sphere so that a
critical point is reached where the sphere suddenly is repelled on the
next positive discharge.
I'm a bit puzzled that any charge could appear on the inside since
charge only appears on the outside surface of spherical conductors per
Faradays' ice pail experiment which led to the modern day Faraday Cage.
His patent shows a cylinder within a cylinder which would work but
according to the Faraday ice pail experiments, a closed sphere would not
work, that is have a charge on the inside, but it could have a charge
only on the outside....like a Van De Graaf....wonder if he's ever built
a spherical capacitor??
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http://www.physics.gatech.edu/demopage/5/5b2010.htm
Charge the big sphere with a rubbed rod. Touch the inside of the sphere
with the proof plane. When proof plane is then touched to electroscope,
(hopefully) no deflection. Next touch the proof plane to the outside of
the sphere, then the electroscope. The electroscope should show a
deflection.
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http://www.physics.gla.ac.uk/gusto/pubsci/exhibits/e3/index.htm
The Faraday cage is a practical application of the effect demonstrated
in school as the Faraday ice-pail experiment. If an ice pail, or any
other hollow conductor is given a charge on its inside, then the charge
will spread all over the outside surface of the conductor in such a way
as to produce no electric field inside.
The Van de Graaff generator uses this effect to produce such a large
potential on the outside surface of its dome. In large Van de Graaff
generators it is possible to have a lab or office actually inside the
dome, and even have people there, while the machine is on! The idea that
a hollow metal conductor will protect the interior from electric fields
can be used using Faraday screens, cans or cages.
-- Jerry Wayne Decker / jdecker@keelynet.com http://keelynet.com / "From an Art to a Science" Voice : (214) 324-8741 / FAX : (214) 324-3501 KeelyNet - PO BOX 870716 - Mesquite - Republic of Texas - 75187