How many times does refraction takes place in glass slab experiment
Answers
In a glass slab,
Let a light ray enters from the top of the slab, from a rare medium or air or vaccum, by making an angle of i.
As glass slab is denser than the other medium ( rare medium ), light ray will refract in the slab by making a refractive angle of r, it will continue moving towards the other side ( place and transparent surface of the slab ). As the ray is continuing moving forward, it will again refract, as it will be crossing from a denser medium to a rare medium. It will cross the other side by, incident angle equal to the refractive angle { when refraction was happened from the top surface }.
Now the refracted ray( after crossing the slab ) will be parallel to the incident ray( when entering in the slab ).
In this experiment, we found that the line which entered in the slab refracts two times by making different incident angle.
1st refraction : when the light ray( incident ray ) enters the glass slab( dense medium ) from air ( rare medium )
2nd refraction : when the incident ray ( refracted ray, from 1st refraction ) enters the air ( rare medium ) from glass slab ( denser medium ).
Hence,
In this experiment, refraction happens two times.