Electric Field Intensity on the axial and equatorial line of an electric dipole

 

Electric Field Intensity at a point on the axial line of an electric dipole

 

This position is also known as ‘End-on position’.

 

What is an axial line?
Axial line is the line joining the centres of positive and negative charges forming an electric dipole.

 

Consider an electric dipole consisting of +q and -q charges separated by a distance 2l.
Consider a point D at a distance ‘r’ from the centre O of the dipole on the axial line of the dipole.

 

6.png

 

Let a unit positive charge be placed at point D.

 

First of all we find electric field at point D due both the charges

 

  • Electric field intensity at D due to +q charge is given by
daum_equation_1434520425525.png
  • Electric field intensity at D due to -q charge is given by
daum_equation_1434520717441.png

 

Applying principle of superposition,the net electric field intensity at point D is given by

 

daum_equation_1434521853172.png
If r >>>>> l
then,
daum_equation_1434522905628.png
Electric Field Intensity at a point on the equatorial line of an electric dipole

 

This position is also known as ‘Broad-side-on position’.

 

What is an equatorial line?
The line perpendicular to the axial line and passes through the centre of the electric dipole length is called an equatorial line.

 

Consider an electric dipole AB consisting of +q and -q charges separated by a distance 2l.

Let P be the point on the equatorial line at a distance r from the centre O of the dipole. A unit positive charge is placed at P.

 

7.png

 

First of all we find electric field at point P due both the charges

 

  • Electric field intensity at P due to +q charge is given by
daum_equation_1434523418116.png

 

  • Electric field intensity at P due to -q charge is given by
daum_equation_1434523373614.png

 

(E1) and (E2 ) are inclined at an angle of 2θ.Applying parallelogram law of vector addition.As
daum_equation_1434523636972.png
The net electric field intensity(E) due to the electric dipole at point P.
daum_equation_1434524534181.png
If r >>>>> l
then,

 

daum_equation_1434524835773.png

5 thoughts on “Electric Field Intensity on the axial and equatorial line of an electric dipole”

Leave a Comment

Adblocker detected! Please consider reading this notice.

We've detected that you are using AdBlock Plus or some other adblocking software which is preventing the page from fully loading.

We don't have any banner, Flash, animation, obnoxious sound, or popup ad. We do not implement these annoying types of ads!

We need fund to operate the site, and almost all of it comes from our online advertising.

Please add academicseasy.com to your ad blocking whitelist or disable your adblocking software.

×