NCERT Solution
Class 12
Physics
Electric Charges and Field
an electric dipole with dipole moment 4 times 10...

Question:
An electric dipole with dipole moment 4 × 10⁻⁹ C m is aligned at 30° with the direction of a uniform electric field of magnitude 5 × 10⁴N C⁻¹. Calculate the magnitude of the torque acting on the dipole.

Answer:

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.

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Question:
An electric dipole with dipole moment 4 × 10⁻⁹ C m is aligned at 30° with the direction of a uniform electric field of magnitude 5 × 10⁴N C⁻¹. Calculate the magnitude of the torque acting on the dipole.

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Question: An electric dipole with dipole moment 4 × 10−9 C m is aligned at 30° with the direction of a uniform electric field of magnitude 5 × 104N C−1. Calculate the magnitude of the torque acting on the dipole.

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Question:
An electric dipole with dipole moment 4 × 10⁻⁹ C m is aligned at 30° with the direction of a uniform electric field of magnitude 5 × 10⁴N C⁻¹. Calculate the magnitude of the torque acting on the dipole.