10, the effect is equivalent to two charged sheets
(at the surfaces of the dielectric normal to the field) with surface charge
densities sp and –sp The electric field in the dielectric then corresponds
to the case when the net surface charge density on the plates is ±(s – sp) That is,
0
P
E
σ
σ
−ε
=
(2 47)
so that the potential difference across the plates is
0
P
V
E d
d
σ
σ
−ε
=
=
(2