Explain the propagation of a ray of light, when it travels from denser to rarer medium.

Ans. 1. When a ray of light travels from an optically denser medium to an optically rarer medium, the ray bends away from the normal.

2. Here the refractive index of the first medium is greater than refractive index of the second medium.
   
3. The greater the value of refractive index, the lesser is the bending of ray away from the normal.

4. The angle of refraction is greater than the angle of the incidence.