To be more concrete, here's a sketch of what I think the field should
look like in the upper right quadrant of a square with four identical
positive charges at the vertices.
--
A. John Mallinckrodt http://www.csupomona.edu/~ajm
Professor of Physics mailto:ajm@csupomona.edu
Physics Department voice:909-869-4054
Cal Poly Pomona fax:909-869-5090
Pomona, CA 91768-4031 office:Building 8, Room 223
This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.