Optics Question 101
Question: A ray of light travels from an optically denser to rarer medium. The critical angle for the two media is C. The maximum possible deviation of the ray will be
[KCET (Engg./Med.) 2002]
Options:
A) $ ( \frac{\pi }{2}-C ) $
B) 2C
C) $ \pi -2C $
D) $ \pi -C $
Show Answer
Answer:
Correct Answer: C
Solution:
When the ray passes into the rarer medium, the deviation is $ \delta =\varphi -0 $ .
This can have a maximum value of $ ( \frac{\pi }{2}-C ) $ for $ \theta =C $ and $ \varphi =\frac{\pi }{2} $ .
When total internal reflection occurs, the deviation is $ \delta =\pi -2 $ , the minimum value of $ \theta $ being $ C. $
The maximum value of $ \delta =\pi -2C $ .
