Optics Question 609
Question: An achromatic combination of lenses is formed by joining
[BHU 1995; Pb. PMT 2000, 04]
Options:
A) 2 convex lenses
B) 2 concave lenses
C) 1 convex lens and 1 concave lens
D) Convex lens and plane mirror
Show Answer
Answer:
Correct Answer: C
Solution:
For an achromatic combination $ \frac{{\omega _{1}}}{f _{1}}+\frac{{\omega _{2}}}{f _{2}}=0 $ i.e. 1 convex lens and 1 concave lens.