the angle of incidence and the angle of emergence are of ..............measures
Answers
It depends on what object the light is incident on. In case of a glass slab, the incident ray is parallel to the emergent ray, that means the angle of incidence is equal to the angle of emergence. The explanation is as follows: When a ray of light is incident on the surface of the glass slab, it undergoes refraction. As the refractive index of the glass slab is denser than that of air, the ray of light bends towards the normal. The same ray of light which is refracted acts as the ray of incidence on the inner surface of the glass slab. it undergoes refraction again and the the ration of the refractive indices between air and glass is same, the emergent ray is parallel to the incident ray. Hence the angles are equal.
In Case of a prism:A ray of light suffers two refraction on passing through a prism. ... The angle through which the emergent ray deviates from the direction of incident ray is called angle of deviation 'd'. As the angle of incidence is increased, angle of deviation 'd' decreases and reaches minimum value.
Hope it helps
the angle of incident ray and angle of emergence Ray are of equal measures.