Q. Light takes $t_{1}$ second to travel a distance $x$ in vaccum and the same light takes $t_{2}$ second to travel 10 $x$ cm in a medium. Critical angle for corresponding medium will be
A) $\sin^{- 1}\left( \frac{10t_{2}}{t_{1}} \right)$
B) $\sin^{- 1}\left( \frac{t_{2}}{{10t}_{1}} \right)$
C) $\sin^{- 1}\left( \frac{10t_{1}}{t_{2}} \right)$
D) $\sin^{- 1}\left( \frac{t_{1}}{10t_{2}} \right)$
Explanation
(c) $c = \frac{x}{t_{1}},v = \frac{10x}{t_{2}}$
$\sin{C^{'} = \frac{1}{\mu} = \frac{v}{c} = \frac{10x}{t_{2}} \times \frac{t_{1}}{x}}$
$C^{'} = \sin^{- 1}\left( \frac{10\ t_{1}}{t_{2}} \right)$ …(i)
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.