DISCUSS THE ELECTRIC FIELD INTENSITY IN AXIAL LINE AND A EQUITORIAL LINE OF ELECTRIC DIPOLE
Axial point:
Consider a system of charges (-q and +q) separated by a distance 2a. Let 'P' be any point on an axis where the field intensity is to be determined.
Electric field at P (E
B) due to +q
Electric field at P due to -q (EA)
Net field at P is given by
Simplifying, we get
As a special case :
Equitorial point:
Consider a dipole consisting of -q and +q separated by a distance 2a. Let P be a point Consider a point P on the equatorial line.
The resultant intensity is the vector sum of the intensities along PA and PB. EA and EB can be resolved into vertical and horizontal components. The vertical compents of EA and EB cancel each other as they are equal and oppositely directed. It is the horizontal components which add up to give the resultant field.
E = 2E
Acos
q
As 2qa = p
As a special case,
We find that at very far off points i.e., 2a < r.< r.
Electricity intensity at an axial point is twice the electric intensity on the equatorial line.