2023 · Q38
Which one of the following statements is correct regarding the travel of a light beam from a rare to a dense medium?
General KnowledgePhysics
- AA light beam travelling from a rare medium to a dense medium slows down and bends towards the normal.
- BA light beam travelling from a rare medium to a dense medium speeds up and bends towards the normal.
- CA light beam travelling from a rare medium to a dense medium slows down and bends away from the normal.
- DA light beam travelling from a rare medium to a dense medium speeds up and bends away from the normal.
Explanation
Going from a rarer to a denser medium, light slows down (v = c/n, since the refractive index is higher) and, by Snell's law, bends towards the normal. Speeding up and bending away from the normal happen only when light goes from a denser to a rarer medium.