Question

Explain the phenomenon of total internal reflection? what are the condition for total innternal reflection

Answer 1

Total internal reflection is the phenomenon which occurs when a propagated wave strikes a medium boundary at an angle larger than a particular critical angle with respect to the normal to the surface. ... The critical angle is the angle of incidence above which the total internal reflection occurs.


For total internal reflection to occur, two conditions must be met: The index of refraction must decrease across the boundary in the direction of light refraction. The angle of incidence of the light ray must exceed the critical angle of the interface. Ray must travel from denser to rarer medium.

Answer 2

when a ray of light travelling from denser medium to rarer medium is incident at the interface of two medium at an angle greater than the critical angle for the two media, the ray is totally reflected back to denser medium, this phenomenon is called total internal reflection. Condition to be followed are the angle of incidence in the denser medium must be greater than the critical angle for the two media and light must travel from an optically denser to an optically rarer medium