If the dipole of moment $2.57 \times 10^{-17} \mathrm{~Cm}$ is placed into an electric field of magnitude $3…

If the dipole of moment $2.57 \times 10^{-17} \mathrm{~Cm}$ is placed into an electric field of magnitude $3.0 \times 10^{4} \mathrm{~N} / \mathrm{C}$ such that the fields lines are aligned at $30^{\circ}$ with the line joining $\mathrm{P}$ to the dipole, what torque acts on the dipole?
  1. $7.7 \times 10^{-13} \mathrm{Nm}$
  2. $3.855 \times 10^{-13} \mathrm{Nm}$
  3. $3.855 \times 10^{-15} \mathrm{Nm}$
  4. $7.7 \times 10^{-15} \mathrm{Nm}$

Solution

$\begin{aligned} \tau &=\left(2.57 \times 10^{-17} \mathrm{Cm}\right)\left(3.0 \times 10^{4} \frac{\mathrm{N}}{\mathrm{C}}\right)\left(\frac{1}{2}\right) \\ &=3.855 \times 10^{-13} \mathrm{Nm} . \end{aligned}$

Asked in: JEE Mains - Electrostatics - Test 5

Practice more Electrostatics questions on Aicharya