A geometric method to determine the electric field due to a uniformly charged line segment

Abstract

A geometrical method to calculate the electric field due to a uniformly charged rod is presented. The result is surprisingly simple and elegant. Using only lengths and angles, the direction of the electric field at any point due to this charge configuration can be graphically determined. The method is not new but seems to have been all but forgotten. A full understanding of this result can lead to a deeper appreciation of symmetry in a seemingly un-symmetric system.