MAGNETIC FIELDS IN MATTER — Edward Purcell & David Morin
Physics — E&M · average-dipole-field-sphere
Problem
By direct integration, show that the average of the dipole field, over the surface of a sphere centered at the dipole, is zero. You will want to work with the Cartesian components of E, but feel free to write these components in terms of spherical coordinates, as in Eq. (10.17).