Question

Write laws of refraction. Explain the same with the help of ray diagram, when a ray of light passes through a rectangular glass slab.

Answer 1

The two laws of refraction are:

1. First Law : The incident ray, the refracted ray and the normal all lie on the same plane.
2. Second Law : The ratio of the sine angle of incident ray and the refracted ray are constant. This law is also known as "Snell's Law".
   
   

In the above diagram, we can see that the incident ray, the refracted ray and the normal all lie on the same plane. It verifies the first law. Similarly, if we take the ratio of the sine angle of incident ray and the refracted ray, we will obtain a constant value. It verifies the second law.