Get Answers to all your Questions

header-bg qa

Q.25) An electric dipole with dipole moment $5 \times 10^{-6} \mathrm{Cm}$ is aligned with the direction of a uniform electric field of magnitude $4 \times 10^5 \mathrm{~N} / \mathrm{C}$. The arpole is then rotated through an angle of $60^{\circ}$ with respect to the electric field. The change inthe potential energy of the dipole is :

A) 1.5J

B) 0.8J

C) 1.0J

D) 1.2J

Answers (1)

best_answer

Given, 

$p =  5 \times 10^{-6} \mathrm{Cm}$
$E = 4 \times 10^5 \mathrm{~N} / \mathrm{C}$
Initial Angle, $\theta_1 = 0^\circ$
Final Angle, $\theta_2 = 60^\circ$

Thus the change in energy is,

$ U = p E\left(\cos \theta_1-\cos \theta_2\right) =  5 \times 10^{-6} \times 4 \times 10^5 (1 - 0.5) = 1\mathrm{~J}$

Hence, the answer is the option 3.

Posted by

Dimpy

View full answer

NEET 2024 Most scoring concepts

    Just Study 32% of the NEET syllabus and Score up to 100% marks