Affiliation:
1. School of Mechanical Engineering National Technical University of Athens 9 Iroon Polytechniou, 157 80 Zografou GREECE
Abstract
This paper revisits the topic of electrostatic field energy due to a pair of the electric charges. Not only point-like charges but also charged spheres of radius R are studied. The self-energies as well as the interaction field energy are discussed in full detail. By combining two alternative didactic paths (one mathematical and the other based on energy conservation principles), it is shown that the interaction field energy (which is a volume integral of the energy density over the infinite space) is always equal to the potential energy, regardless of the nature of the electrical charges. For these two characteristic cases of electric charges (i.e., point-like and uniformly charged spheres), the location and the amount of the major part of the interaction field energy is discussed; the relevant factoids are documented in the form of two compact theorems in the Appendix. The case of non-uniformly charged spheres (i.e., spherical conductors) is also discussed to some extent. In addition to this general presentation, the particular case of the electric dipole is discussed, as a special case, accompanied with many numerical results.
Publisher
World Scientific and Engineering Academy and Society (WSEAS)
Subject
Electrical and Electronic Engineering,Building and Construction
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