Refraction Of Light

Refractive index of glass with respect to air Critical angle
...(i)
When a ray of light incident from air on the glass with angle of incidence . If be the angle of refraction, then by Snell's law,

[from E(i))]

Step 1: Condition for parallel emergence.
When a ray passes through multiple media and emerges parallel to the incident ray, the net angular deviation must be zero.
Step 2: Relation of refractive indices.
Using the law of refraction at successive interfaces, the refractive index between two media is given by the ratio of their absolute refractive indices.
Step 3: Deriving the relation.

Step 4: Conclusion.
Hence, the correct relation is

We can use Snell's law to solve this problem: Where: - is the angle of incidence, - is the angle of refraction, - (refractive index of air), - (refractive index of water). Substitute the known values: Thus, the angle of refraction in water is .