Question

The critical angle for diamond $(refractiveindex=2.4)$ is

• A. ${28.62}^{\circ }$
• B. ${25.62}^{\circ }$
• C. ${23.62}^{\circ }$
• D. ${24.62}^{\circ }$

Answer 1

The correct option is D

${24.62}^{\circ }$

Applying Snell's law :

$\mu =\frac{sin{90}^{\circ }}{sin{\theta }_C}=\frac{1}{sin{\theta }_C}\Rightarrow 2.4=\frac{1}{sin{\theta }_C}\Rightarrow {\theta }_C=si{n}^{-1}\left(\frac{1}{2.4}\right)={24.62}^{\circ }$

Hence, the correct answer is ${24.62}^{\circ }$