(a) Verify by direct calculation that the static tangential electric field (3.186) in a circular opening in a flat conducting plane, when inserted into the defining equation (9.72) for the electric dipole moment peff, leads to the expression (9.75).
(b) Determine the value of iμωmeff given by (9.72) with the static electric field in part a.
(c) Use the static normal magnetic field (5.132) for the corresponding magnetic boundary problem with a circular opening to compute via (9.74) the magnetic dipole moment meff and compare with (9.75).
(d) Comment on the differences between the results of parts b and c and the use of the definitions (9.72) in a consistent fashion. [See Section 9 of the article, Diffraction Theory, by C. J. B. Bouwkamp in Reports on Progress in Physics, Vol. 17, ed. A. C. Strickland, The Physical Society, London (1954).]