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A microscope is focussed on an ink mark ...

A microscope is focussed on an ink mark on th 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 downwards

Text Solution

Verified by Experts

The correct Answer is:
A, C, D
`(h_i)/(h_0)=(n_((Air)))/(n_((Glass)))=(1)/(1.5)`
`therefore h_i=(1)/(1.5)xxh_0`
`=(1)/(1.5)xx3`
`therefore h_i=2` cm
`therefore` Microscope be moved =3-2=1 cm upward
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