Why for total internal reflection light must travel from denser to rarer medium? please tell me sir

Asked by gopalsahasubhri | 4th Feb, 2019, 08:34: AM

Expert Answer:

As you know when light ray travel from denser to rarer medium its bends away from the normal. That it will try to touch The surface of contact between two different media if it has been incident on a particular angle.
If light ray travel from rarer to denser it bend towards the normal which means it will never touch the surface of contact. 
Diagram is attached. 

Answered by Ankit K | 4th Feb, 2019, 07:04: PM