A narrow light beam in crown glass (index ) is incident on a flat interface with a…
PHYSICS · Multi-part · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments
Problem
A narrow light beam in crown glass (index 1.52) is incident on a flat interface with a transparent gas. The angle of incidence measured from the normal is 40∘, and the beam refracts into the gas at 70∘.
Respond fully to each part, showing all steps and clearly labeling final answers.
(a) Determine the index of refraction of the gas.
(b) Calculate the speed of light in the gas.
(c) If light were to travel from the gas back into the glass, determine whether a critical angle for total internal reflection would exist at the gas–glass boundary. If it does, compute its value; if it does not, explain why.