In your laboratory you trace the path of light rays through a glass slab for different values of angle of incidence (∠i) and in each case measure the values of the corresponding angle of refraction (∠r) and angle of emergence (∠e). On the basis of your observation your correct conclusion is:
(a) ∠i is more than ∠r, but nearly equal to ∠e
(b) ∠i is less than ∠r, but nearly equal to ∠e
(c) ∠i is more than ∠e, but nearly equal to ∠r
(d) ∠i is less than ∠e, but nearly equal to ∠r
Answer
- When light enters from air to glass, it bends towards the normal
- Hence, angle of refraction is less than angle of incidence
- When light leaves the surface of glass to air
- It bends away from the normal
- This, angle of emergence is almost equal to angle of incidence
So, the correct answer is (a) - ∠i is more than ∠r, but nearly equal to ∠e