question_answer

A ray of light travels from an optically denser to a rarer medium. The critical angle for the two media is C. The maximum possible deviation of the ray will be:

A)  2C

B)  \[\frac{\pi }{2}-C\]

C)   \[\pi \]-C

D)  \[\pi -2C\]

Correct Answer: B

Solution :

 OA = incident ray \[\Delta S=\] interface which separates the two medium. OB = actual path of the incident ray. \[\angle C=\]critical angle. \[\angle QOB\]is also \[=\angle C\] After incidence ray refract towards OS. \[\therefore \]Deviation \[(\delta )=\angle BOS\] \[=\frac{\pi }{2}-C\]