Question

At what angle should a ray of light be incident on the face of refracting

Answer 1

The incident, refracted, and emergent rays associated with a glass prism ABC are shown in the given figure.



Angle of prism, ∠A = 60°

Refractive index of the prism, µ = 1.524

= Incident angle

= Refracted angle

= Angle of incidence at the face AC

e = Emergent angle = 90°

According to Snell’s law, for face AC, we can have:



It is clear from the figure that angle



According to Snell’s law, we have the relation:



Hence, the angle of incidence is 29.75°.