Question

Light propagates faster through a medium “A” than medium “b”

1. Which of these medium has a higher optical density ?
2. State the condition under which no change in direction of propagation of a light ray would take place when it passes through medium “a” to medium “b”

Answer 1

Answer:

1) The medium b has higher optical density.

2) If the optical densities of both A and B are same.

Explanation:

1. The refractive index of a material determines the number of times the velocity of light in that material is slower than the velocity of light in a vacuum.
2. The higher refractive index means slower propagation of the light in that medium.
3. The refractive index of the medium determines the optical density of the medium.
4. If the material has a higher refractive index, then its optical density is high.
5. If the material has a low refractive index, then its optical density is low.
6. The light bends towards the normal while refracting through the medium from a lower optical density medium to the higher optical density medium.
7. If both the mediums has the same optical density, the direction of propagation doesn't change.