Ludwig wrote:
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In my opinion charges are not spread equally when plates are far away
from each other. They would be distributed uniformly on spheres (away
from walls, floors, etc.) but on thin circular plates, for example, they
must be uniformly distributed along the rims. For the same reason (mutual
repulsion to minimize potential energy) a single rectangular plate will
concentrate its electrons (or "holes") near corners. Thus an isolated
circular plate of very large radius will create the field which is the
same as that due to a uniform circular loop (a thin wire).
Ludwik
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Ludwig,
You're going to have a tough time getting the field inside these plates
to be zero!