suppose I have a charge q at (x=-d) and a charge q at (x=+d). the force between them is q^2/(4*pi*(eps_0)*4*d^2). now, I insert a dielectric (K) between (-d/2<x<d/2), and try to calculate the force now... it seems like it would be the same but it sounds strange... If I use the D field, it is not effected by the dielectrics, and thus I can see that the electrical field E is the same as before (D/eps_0) and thus the force is the same... could it be?????