22 A dielectric develops a net dipole
moment in an external electric field (a) Non-polar
molecules, (b) Polar molecules Rationalised 2023-24
Electrostatic Potential
and Capacitance
67
every volume element Dv of the slab has a dipole moment
P Dv in the direction of the field The volume element Dv  is
macroscopically small but contains a very large number of
molecular dipoles