JEE Main201912 Jan 2019Morning ShiftPhysicsElectrostaticsActual
Determine the electric dipole moment of the system of three charges, placed on the vertices of an equilateral triangle, as shown in the figure:
Options
- A3 q l j ^ - i ^ 2
- B- 3 q l j ^
- C2 q l j ^
- Dq l i ^ + j ^ 2
Correct answer
B. - 3 q l j ^
Step-by-step solution
P → 1 = q l P → 2 = q l Angle between them 60 o ∴ Resultant dipole moment P = q l 2 + q l 2 + 2 q l 2 cos ⁡ 60 o = 3 ql As P → 1 = P → 2 direction of resultant is along negative y axis thus option is - 3 q l j ^