I think that we beginning to make this problem difficult. We can
probably calculate the potential distribution is space due to a flattened
coffee can lid isolated in space with 100nC on it. We can do the same
for one with -10nC on it. The charge will probably be distributed so
that both plates have an excess of charge at the edge. The appropriate
derivatives will yeild the field.
Now we have to move them together. Presumably, the charge distributions
will change and the plates will attract one another during the move. I
have no idea how to model the changes in the potential. Apparently, the
potential at infinity would approach that of a point charge with 90nC and
a capacitor with +10nc on one plate and -10nC on the other. The latter
will probably fall off much faster than the former--does that help?
W. Barlow Newbolt 540-463-8881 (telephone)
108 Parmly Hall 540-463-8884 (fax)
Washington and Lee University newbolt.w@fs.science.wlu.edu
Lexington, Virginia 24450 wnewbolt@liberty.uc.wlu.edu
"The best measure of a man's honesty isn't his income tax return. It's the
zero adjust on his bathroom scale"
Arthur C. Clarke