Q21E - University Physics with Modern Physics

Question

Light is incident along the normal on face AB of a glass prism of refractive index 1.52, as shown in Fig. E33.21. Find the largest value the angle$\mathbf{\infty }$can have without any light refracted out of the prism at face AC if (a) the prism is immersed in air and (b) the prism is immersed in water.

                                

Step-by-Step Solution

Answer

1. The angle $\infty$, if the prism is immersed in air $48.86°$
2. The angle $\infty$, if the prism is immersed in water $28.72°$

Step 1: Snell’s law

Snell's law determines the degree of refraction as well as the relationship between the angle of incidence, angle of refraction, and refractive indices of two media.

Here;

Critical Angle-Beyond which light rays traveling through a thicker media to the surface of a less dense medium are no longer refracted but completely reflected

Total Internal Reflection-When the angle of incidence surpasses the critical angle, a light ray reaches an interface with less dense material and is completely reflected.

                     

Step 2: If the prism is immersed in air

         (b)  Medium 1 is glass

           Medium 2 is air

Hence, the angle $\infty$if the prism is immersed in water $28.72°$