Q. The electric field at a point due to an electric dipole, on an axis inclined at an angle $\theta( < 90{^\circ})$to the dipole axis, is perpendicular to the dipole axis, if the angle $\theta$ is
A) $\tan^{- 1}\left( \frac{1}{\sqrt{2}} \right)$
B) $\tan^{- 1}\left( \sqrt{2} \right)$
C) $\tan^{- 1}\left( \frac{1}{2} \right)$
D) $\tan^{- 1}{(2)}$
Explanation
(b) $\alpha + \theta = 90{^\circ}$
$\tan{\alpha = \frac{1}{2}\tan\theta}$
$\tan{\theta = 2\tan(90{^\circ} - \theta)}$
$\tan^{2}{\theta = 2}$
$\theta = \tan^{- 1}\left( \sqrt{2} \right)$
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.