Optics Question 764
Question: A microscope is focussed on a coin lying at the bottom of a beaker. The microscope is now raised up by 1 cm. To what depth should the water be poured into the beaker so that coin is again in focus? (Refractive index of water is $ \frac{4}{3} $ )
[BHU 2003]
Options:
A) 1 cm
B) $ \frac{4}{3} $ cm
C) 3 cm
D) 4 cm
Show Answer
Answer:
Correct Answer: D
Solution:
Suppose water is poured up to the height h, So $ h( 1-\frac{1}{\mu } )=1 $
$ \Rightarrow h=4\ cm $
