Three charges are arranged on the vertices of an equilateral triangle as shown in figure (29.E6) find the dipole moment of the combination.

Explanation

`Let -qand -q are placed at A and C `
where 2q on B
` So, length of A=d `
So, `the dipole moment =(qxxd)=P `
So, resultant dipole moment
` P=[(qd)^2+(qd)^2+2qd qdcos60]^(1/2) `
` =[d^2q^2+d^2q^2+2d^2q^2xx1/2]^(1/2) `
` =[3q^2d^2]^(1/2)=sqrt(3)qd`