Optics Question 596
Question: An object is placed at a distance of 20 cm from a convex lens of focal length 10 cm. The image is formed on the other side of the lens at a distance
[CPMT 1971; RPET 2003]
Options:
A) 20 cm
B) 10 cm
C) 40 cm
D) 30 cm
Show Answer
Answer:
Correct Answer: A
Solution:
$ \frac{1}{f}=\frac{1}{v}-\frac{1}{u} $ (Given $ u=-20 $ cm, $ f=10 $ cm, $ v=? $ )
$ \therefore $ $ \frac{1}{10}=\frac{1}{v}-\frac{1}{(-20)}\Rightarrow v=20cm $
