Speaking of textbooks, all of them seem to explain the reduction of potential
difference when a dielectric is inserted in an isolated capacitor in terms of
electric fields, surface charges on the dielectrics, and so on.
Several years ago it dawned on me that every one of the dipoles in the dielectric
has its negative end closer to the positive plate, and its positive end closer to the
negative plate.
I now prefer to explain the reduction of delta-V directly from the locations of the
dipole charges, rather than discussing electric fields between the plates. Once
it's clear that the potential must be lower, then so must the average electric field
be lower as well.
Any comments?
--
Mike
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Mike Moloney moloney@nextwork.rose-hulman.edu
Dept of Physics & Applied Optics (812) 877 8302
Rose-Hulman Institute of Technology Terre Haute, IN 47803 http://www.rose-hulman.edu/~moloney