Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <A123X-at-aol-dot-com> I understand that in lossy dielectrics they waste the energy into heat, but I don't really understand what causes this to happen. What causes it to occur more in some dielectric than others? Also does only the surface of the dielectric affect loss? Is the dielectric constant only that of the surface?