Q. $\lambda_{a}\ and\ \lambda_{m}$ are the wavelength of a beam of light in air and medium respectively. If $\theta$ is the polarising angle, the correct relation between $\lambda_{a},\lambda_{m}\ and\ \theta$ is
A) $\lambda_{a} = \lambda_{m}\tan^{2}\theta$
B) $\lambda_{m} = \lambda_{a}\tan^{2}\theta$
C) $\lambda_{a} = \lambda_{m}\cot\theta$
D) $\lambda_{m} = \lambda_{a}\cot\theta$
Explanation
(d) We know, $\lambda_{m} = \frac{a}{\mu}\ and\ \mu = \tan\theta$
$\therefore\ \ \lambda_{m} = \frac{\lambda_{a}}{\tan\theta} = \lambda_{a}\cot\theta$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.