An electric dipole with dipole moment 5×10⁻⁶ C m is aligned with the direction of a uniform electric field of magnitude 4×10⁵ N/C. The dipole is then rotated through an angle of 60° with respect to the electric field. The change in the potential energy of the dipole is:

Question

Accepted Answer

(2) 1.0 J. U=-pE cos θ and pE=5×10⁻⁶×4×10⁵=2 J. Δ U=U_60°-U_0°=-pE cos 60°+pE cos 0°=pE(1-cos 60°). Δ U=2×1/2=1.0 J.

An electric dipole with dipole moment 5×10⁻⁶ C m is aligned with the direction of a uniform electric field of magnitude 4×10⁵ N/C. The dipole is then rotated through an angle of 60° with respect to the electric field. The change in the potential energy of the dipole is:

Step-by-step solution

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