$A$ point source of light is placed at a distance $h$ below the surface of a large deep lake. What is the percentage of light energy that escapes directly from the water surface if the refractive index $\mu$ of the water is $4/3$ (in $\%$)? (Neglect partial reflection)

On the hypotenuse of a right-angled prism $(30^{\circ}-60^{\circ}-90^{\circ})$ with a refractive index of $1.50$,a drop of liquid is placed as shown in the figure. Light is allowed to fall normally on the short face of the prism. In order for the ray of light to undergo total internal reflection at the hypotenuse,what is the maximum value of the refractive index of the liquid?

$A$ glass prism of refractive index $1.5$ is immersed in water (refractive index $\frac{4}{3}$) as shown in the figure. $A$ light beam incident normally on the face $AB$ is totally internally reflected at the face $AC$ to reach the face $BC$,if:

$A$ beam of light consists of red,green,and blue colors. It is incident on the $AB$ face of a right-angled prism as shown in the figure. The refractive indices for red,green,and blue colors are $1.39$,$1.44$,and $1.47$ respectively. What will a person see when looking at the $AC$ surface of the prism?

The refractive index of the medium is:

$A$ ray of light is incident at an angle $i$ from a denser to a rarer medium. The reflected and the refracted rays are mutually perpendicular. The angle of reflection is $r$ and the angle of refraction is $r'$. Then the critical angle $C$ will be: