Optics Question 691
Question: The focal lengths for violet, green and red light rays are $ f _{V},f _{G} $ and $ f _{R} $ respectively. Which of the following is the true relationship
[BHU 2004; CBSE PMT 1997]
Options:
A) $ f _{R}<f _{G}<f _{V} $
B) $ f _{V}<f _{G}<f _{R} $
C) $ f _{G}<f _{R}<f _{V} $
D) $ f _{G}<f _{V}<f _{R} $
Show Answer
Answer:
Correct Answer: B
Solution:
$ f\propto \frac{1}{\mu -1} $ and $ \mu \propto \frac{1}{\lambda } $
