If ψo1 = ψo2 = ψo we get:
 |
(9.48) |
Under Deryaguin approximation electrical potential energy of spherical particle can be written as
 |
(9.49) |
From equation (9.47) substituting value of GEL in equation (9.49) we have
where R is replaced by  for particles of different diameter. If ψo1 = ψo2 = ψo we get:
|
(9.50) |
Fig. 9.5: Electric force between two particles with distance.
From above figure we see that for same type of potential on the two surface, FR will be repulsive for d> Dc but will be attractive for d< Dc. To avoid the distortion of potential field, 2nd plate is kept where the potential of 1st plate is equal to that of 2nd plate.
|
