Three charges are arranged on the vertices of n equilateral triangle as shown in figure. Find the dipole moment of the combination.
Given:
Distance between two charges :d
In the diagram, the dipole moments 
are extended and resolved into the resultant component 
.
Formula used:
The resultant 
is given as vector sum of 
As angle between 
and 
is 30° , the value of the resultant:
As p1=p2, the resultant due to 
is :
We know that:
p=qd
Where p is the dipole moment, q is the magnitude of charges and d is the distance between the charges forming the dipole.
Substituting, the resultant dipole moment is:
Hence, dipole moment of the combination is qd√3
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