Optics Question 656
Question: In a plano-convex lens the radius of curvature of the convex lens is 10 cm. If the plane side is polished, then the focal length will be (Refractive index = 1.5)
[CBSE PMT 2000; BHU 2004]
Options:
A) 10.5 cm
B) 10 cm
C) 5.5 cm
D) 5 cm
Show Answer
Answer:
Correct Answer: B
Solution:
$ f=\frac{R}{2(\mu -1)}=\frac{10}{2(1.5-1)}=10cm $
