Question

Three point charges of $+ 2q, + 2q$ and $- 4q$ are placed at the corners $A, B$ and $C$ of an equilateral triangle $ABC$ of side $'x'$. The magnitude of the electric dipole moment of this system is

• A. $2\,qx$
• B. $2 \sqrt{3} \,qx$
• C. $3 \sqrt{2} qx$
• D. $3 \, qx$

Answer 1

Answer: (B)

$2 \sqrt{3} \,qx$

Answer 2

According to question. The magnitude of electric dipole moment $P_{\text {net }}=\sqrt{p^{2}+p^{2}+2 p p \cos 60^{\circ}}$ $=\sqrt{2 p^{2}+2 p^{2} \times \frac{1}{2}}$ $=\sqrt{3} \cdot p$ We know that, $p=2 q \cdot x$ $[\because p=q \cdot I]$ $=\sqrt{3} \cdot 2q x=2 \sqrt{3} \,q x$