Question

Find net dipole moment of given charge configuration.

• A. $1.4qa$
• B. $3qa$
• C. $3qa$
• D. $2.8qa$

Answer 1

The correct option is D $2.8qa$

Let us assume that the given configuration is a combination of three set of dipoles. Their net dipole moment will be,
$p_{net}=(qa\hat{i}+qa\hat{j})+qa\sqrt{2}\sin {45}^o\hat{j}+qa\sqrt{2}\cos {45}^o\hat{i}$
$=(qa\hat{i}+qa\hat{j})+qa\hat{i}+qa\hat{j}$
$=(2qa\hat{i}+2qa\hat{j})=2.8qa$