Define critical angle for a pair of media.

Asked by saanvireddy0205 | 6th Aug, 2021, 09:21: AM

Expert Answer:

When a light ray passes from a medium of high refractive index to another medium of low refractive index ,
if the angle of refraction becomes 90o for the given angle of incidence at the the interface of two medium ,
then this angle of incidence is known as critical angle. 
 
When angle of incidence is less than critcal angle, refraction takes place
 
When angle of incidence is critical angle , refracted ray passes through the line of interface of two medium. 
 
When angle of incidence is greater than crictical angle , there will not be refraction into other medium,
only total internal reflection in the initial medium .
 

Answered by Thiyagarajan K | 6th Aug, 2021, 10:40: AM