Question
Question: A ray of light from denser medium strikes a rarer medium at angle of incidence i. The reflected and ...
A ray of light from denser medium strikes a rarer medium at angle of incidence i. The reflected and the refracted rays make an angle of 90ŗ with each other. The angles of reflection and refraction are r and r' respectively. The critical angle is –
A
sin–1 (tan r)
B
sin–1(tani)
C
sin–1 (tan r')
D
tan–1(sini)
Answer
sin–1(tani)
Explanation
Solution
r + r' = 900
sin c = 
= 
sin c = 
= 
= 
r = i
c = sin–1 (tan i)