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A microscope is focussed on an ink mark ...

A microscope is focussed on an ink mark on the top of a table. If we place a glass slab of 3 cm thick on it, how should the microscope be moved to focus the ink spot again? The refractive index of glass is 1.5

A

2 cm upwards

B

2 cm downwards

C

1 cm upwards

D

1 cm upwards

Text Solution

Verified by Experts

The correct Answer is:
C
(c ) Given, n=1.5, and `h_(o)=3cm`
Refractive index, `n=h_(o)/h_(i) rArr 1.5=3/h_(i)`
Apparent depth , `h_(i)=3/1.5=2 cm`
Hence, 3-2=1 cm upwards.
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