Question
Physics Question on Optical Instruments
The angle of a prism is 'A'. One of its refracting surfaces is silvered. Light rays falling at an angle of incidence 2A on the first surface returns back through the same path after suffering reflection at the silvered surface. The refractive indexµ, of the prism is
A
2cos A
B
21cosA
C
tan A
D
2 sin A
Answer
2cos A
Explanation
Solution
The correct option (A): 2cos A