Question

A ray of light is incident on a set of media at an angle 60°. The angle of refraction is different for different media as shown.
In which medium the speed of light is slowest?

• A. 1
• B. 2
• C. 3
• D. Same in all

Answer 1

The correct option is C 3

Light, while entering a denser medium from a rarer medium, gets slowed down and bends towards the normal. The bending towards the normal is more if the second medium in refraction has higher optical density. Here, the most dense medium is medium 3 as light bends by the maximum amount.
Speed of light is lower in optically denser media. Therefore, speed of light is minimum in medium 3.