Electric fields produced by coplanar point charges have often been represented by field line diagrams that depict two‐dimensional slices of the three‐dimensional field. Serious problems with these ‘‘conventional’’ field line diagrams (CFLDs) have been overlooked. Two of these problems, ‘‘equatorial clumping’’ and ‘‘false monopole moment,’’ occur because a two‐dimensional slice lacks information vital to the accurate representation of an inherently three‐dimensional field. Equatorial clumping causes most CFLDs to exhibit unphysical behavior such as irregular spacing between field lines terminating on negative charges. CFLDs can also mistakenly indicate that a neutral charge distribution has a significant monopole moment. Such phenomena make the visual estimation of local field strengths impossible and render CFLDs of little utility for representing three‐dimensional fields. While these ‘‘projection’’ problems can be avoided by using two‐dimensional field line diagrams to represent two‐dimensional (1/r) electric fields, or by using three‐dimensional field line diagrams to represent three‐dimensional fields, other forms of distortion generally remain.

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