In the figure, a ray of light is perpendicular to the face $A B$ of a glass prism $(μ = 1.52)$ .
Find the value of $θ$ so that the ray is totally reflected at face $A C$ , if the prism is immersed in water $(μ = 1.33)$ . Given $sin 6 1^{\circ} = 0.875$

Question

TestHub · Accepted Answer

Given, μ g ​ = 1.52 , μ w ​ = 1.33 , θ = ? Apply Snell's law at point D , ​ μ g ​ sin i c ​ = μ w ​ sin 9 0 ∘ ⇒ sin i c ​ = μ g ​ μ w ​ ​ = 1.52 1.33 ​ ​ ⇒ i c ​ = sin − 1 ( 1.52 1.33 ​ ) = 6 1 ∘ From figure, θ + i c ​ = 9 0 ∘ ⇒ θ = 9 0 ∘ − 6 1 ∘ = 2 9 ∘ ≈ 3 0 ∘

Physics - Geometrical Optics Question with Solution | TestHub

Options:

Doubts & Discussion