Re: Grounding (fwd)
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Date: Thu, 05 Nov 1998 15:25:21 -0800 From: Michael Motyka <mmotyka@lsil.com> Subject: Re: Grounding
*** Electricity runs from a high-potential point to ground. If it isn't grounded it radiates away into space where it can be detected. If the Faraday Cage isn't grounded it simply acts as a parasitic oscillator and re-emits the signal from inside, though at a lower amplitude. Remember, charge rests on the *OUTSIDE* of a object so that any charge picked up internaly gets passed to the outside surface. ***
Consider a battery-powered spark gap inside a copper box. Lots of beautiful wideband noise. I refuse to ground my copper box. I'm going to suspend it from a weather balloon over Menwith Hill.
And you'll build a hell of a charge on it which will travel down the connecting cable that you have pounded into the Earth.
The solutions to the wave equation inside the cavity have a real part ~0 in the exponent.
It's not a question of a Schroedingers Wave Equation, it's a question of Maxwell's Equations.
The boundary condition at the inside surface of the copper box splices together the solutions in the cavity and inside the conductor.
What conductor? The shell is equipotential unless you're trying to play head games with me so there follows there can be no current flow through it except radialy to the outside of the sphere. Let's walk through it using your model.... The spark gap generates sparks and that builds up free electrons in the space inside the sphere (whether it is gas filled or a vacuum is irrelevant). As that charge builds up it will be all of one type, electrons. Now the electrons repel each other and therefor move in a circular motion with the spark gap as the center. They strike the surface of the sphere and tunnel through to the outside surface where they reside. The amount of charge at any one point is related to the curvature of the surface at that point. Since a sphere is constant curvature the charge will be evenly distributed. It will continue to build up so long as you supply power to the spark gap. In an ideal world it will get bigger and bigger. In the real world at some point insulation breaks down and normal current flow takes place. As to the 3 Laws of Thermodynamics, you should use Heinz Pagels (RIP) as they are much funnier and a lot easier to understand and apply: 1. You can't break even 2. You can't get ahead 3. You can't quit the game ____________________________________________________________________ To know what is right and not to do it is the worst cowardice. Confucius The Armadillo Group ,::////;::-. James Choate Austin, Tx /:'///// ``::>/|/ ravage@ssz.com www.ssz.com .', |||| `/( e\ 512-451-7087 -====~~mm-'`-```-mm --'- --------------------------------------------------------------------
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Jim Choate