JEE Main 2025 — Electrostatics Question with Solution

Two small spherical balls of mass 10 g each with charges $-2\mu \mathrm{C}$ and $2\mu \mathrm{C}$, are attached to two ends of very light rigid rod of length 20 cm . The arrangement is now placed near an infinite nonconducting charge sheet with uniform charge density of $100\mu \mathrm{C}/{\mathrm{m}}^2$ such that length of rod makes an angle of $30^{\circ }$ with electric field generated by charge sheet. Net torque acting on the rod is: (Take ${\epsilon }_{\mathrm{o}}:8.85\times 10^{-12}{\mathrm{C}}^2/{\mathrm{Nm}}^2$ )