Question
Physics Question on Refraction of Light
A ray of light is incident on an equilateral glass prism placed on a horizontal table. For minimum deviation which of the following is true ?
A
PQ is horizontal
B
QR is horizontal
C
RS is horizontal
D
Either PQ or RS is horizontal
Answer
QR is horizontal
Explanation
Solution
During minimum deviation the ray inside the prism is parallel
to the base of the prism in case of an equilateral prism.
Hence, the correct option is (b).