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Physics/Electric field exterior to capacitors


Has it been observed that charged high capacitance capacitors generate a large positive electrostatic charge on their exterior insulating surfaces?

Has it been observed that charged high capacitance capacitors attract negative electrostatic charges to their exterior insulating surfaces?

Generally they only produce small fringing fields near their edges unless they have a large total static charge added to them in some way.  Aside from the use of a huge Van de Graaf generator, I have no idea how or why one would give a net charge to a capacitor...and it would be a very small charge indeed.  In general, only the fringing fields would attract charges, and only towards the edge of the oppositely-charged plate...but this effect is extremely minimal under the worst conditions.  A huge open capacitor can be used (and they are) to precipitate ash from coal fired power plant smoke stacks, but not to the outer surface where there is no real field.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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