Q. A diver at a depth of 12m in water$\left( \mu = \frac{4}{3} \right)$ sees the sky in a cone of semivertical angle
A) $\sin^{- 1}\begin{array}{r}
\left( \frac{4}{3} \right)
\end{array}$
B) $\tan^{- 1}\left( \frac{4}{3} \right)$
C) $\sin^{- 1}\begin{array}{r}
\left( \frac{3}{4} \right)
\end{array}$
D) $90{^\circ}$
Explanation
(c) $C = \sin^{- 1}\left( \frac{1}{\mu} \right) = \sin^{- 1}\left( \frac{3}{4} \right)$
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.