An electric dipole with dipole moment $3 × 10^{-9} Cm$ is aligned at 30° with the direction of uniform electric field of magnitude $6 × 10^4 NC^{-1}$. What will be the magnitude of the torque acting on the dipole?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → $9×10^{-5} Nm$
The torque ($τ$) acting on an electric field ($\vec E$) is,
$τ=pE\sin θ$
$=(3×10^{-9})×(6×10^4)×\sin(30°)$
$=9×10^{-5} Nm$