Optics Question 662
Question: A thin lens made of glass of refractive index m = 1.5 has a focal length equal to 12 cm in air. It is now immersed in water $ ( \mu =\frac{4}{3} ) $ . Its new focal length is
[UPSEAT 2002]
Options:
A) 48 cm
B) 36 cm
C) 24 cm
D) 12 cm
Show Answer
Answer:
Correct Answer: A
Solution:
$ f _{w}=4\times f _{a}=4\times 12=48\ cm. $
