Question

Relation between critical angle of water and the glass is :

• A. $C_w=C_g=0$
• B. $C_w=C_g$
• C. $C_w>C_g$
• D. $C_w<C_g$

Answer 1

The correct option is C $C_w>C_g$

The critical angle is given by

$C=si{n}^{-1}\left(\frac{1}{\mu }\right)$

The refractive index of air ${\mu }_w=1.33$

$C_w=si{n}^{-1}\left(\frac{1}{1.33}\right)={48.75}^0$

The refractive index of water, ${\mu }_g=1.517$

$C_g=si{n}^{-1}\left(\frac{1}{1.517}\right)={41.23}^0$

$C_w>C_g$

The correct option is C.