A light ray enters from medium A to medium B as shown in Figure 10.2. The refractive index of mediumB relative to A will be
(a) greater than unity
(b) less than unity
(c) equal to unity
(d) zero
Answer
Relative refractive index = N 2 /N 1
In this case, Relative refractive index, ղ = N b /N a
- Going from Medium A to B, light ray bends towards the normal
- When an incident ray passes from rarer to denser medium , it bends toward the normal.
- Hence, Medium B is denser than Medium A
- So, we can say that N b > N a .
- Thus, Relative refractive index, ղ = N b /N a > 1
So, the correct answer is (a)
