Q15. Critical angle of incidence for a pair of optical media is $45 ^ { \circ }$. The refractive indices of first and second media are in the ratio: (1) $1 : \sqrt { 2 }$ (2) $\sqrt { 2 } : 1$ (3) $2 : 1$ (4) $1 : 2$
Q15. Critical angle of incidence for a pair of optical media is $45 ^ { \circ }$. The refractive indices of first and second media are in the ratio:\\
(1) $1 : \sqrt { 2 }$\\
(2) $\sqrt { 2 } : 1$\\
(3) $2 : 1$\\
(4) $1 : 2$