Total Internal Reflection

• The phenomenon due to which a ray of light, while traveling from optically denser medium to optically rarer medium, gets reflected into optically denser medium, at the surface of separation.
• For total internal reflection:

(i) rays of light must travel from optically denser medium to optically rarer medium

(ii) the angle of incidence in optically denser medium, must be greater than critical angle.

• Angle of incidence in a denser in a denser medium for which angle of refraction in rarer medium is 90 degree is called critical angle.
• The critical angle for water is 48 degree
• The critical angle for glass is 42 degree.