JEE Main 2026 — Jan 24, Shift 1 — Physics solution

JEE Main2026Jan 24, Shift 1Physics

Three charges $+ 2 q$ , $+ 3 q$ and $- 4 q$ are situated at $(0, - 3 a)$ , $(2 a, 0)$ and $(- 2 a, 0)$ respectively in the xy plane. The resultant dipole moment about origin is____

A
$2 q a (3 \hat{j} - \hat{i})$
B
$2 q a (3 \hat{i} - 7 \hat{j})$
C
$2 q a (7 \hat{i} - 3 \hat{j})$
D
$2 q a (3 \hat{j} - 7 \hat{i})$

Solution

For a system of point charges, the dipole moment about the origin is $p = \sum_{i} q_{i} r_{i}$ .

$p = (+ 2 q) (- 3 a \hat{j}) + (+ 3 q) (2 a \hat{i}) + (- 4 q) (- 2 a \hat{i})$

$= - 6 q a \hat{j} + 6 q a \hat{i} + 8 q a \hat{i}$

$= 14 q a \hat{i} - 6 q a \hat{j} = 2 q a (7 \hat{i} - 3 \hat{j})$ .

← Back to full paper

Practice more Physics

Concept-wise practice with instant solutions on Fundamenthol.

Start practicing →