Question

An electric dipole with dipole moment 2×10–¹9cm is aligned at 30° with the direction of uniform electric field of magnitude 4×10⁴NC–¹. The magnitude of the torque acting on the dipole is

Answer 1

Quest :-

An electric dipole of dipole moment 4 × 10-9 Cm is placed at 30° with a uniform electric field of magnitude of 5 × 104 NC-1.

Ans :-

Electric dipole moment, p = 4 × 10−9 C m (Given)

Angle made by p with a uniform electric field, θ = 30° (Given)

Electric field, E = 5 × 104 N C−1 (Given)

Torque acting on the dipole is given by the relation,

τ = pE sinθ

= 4 × 10-9 × 5 × 104 × sin 30

= 20 × 10-5 × 1 half

= 10-4 Nm

Therefore, the magnitude of the torque acting on the dipole is 10−4 N m.