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A microscope is focused on a mark on a p...

A microscope is focused on a mark on a piece of paper and then a slab of glass of thickness `3cm` and refractive index `1.5` is placed over the mark. How should the microscope be moved to get the mark in focus again ?

A

`1cm` downward

B

`2cm` upward

C

`1cm` upward

D

`4.5cm` downward

Text Solution

Verified by Experts

The correct Answer is:
C

Shift of O by slab`=3(1-(1)/(3//2))=1cm` above O
(Here O is outside slab)
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CP SINGH-REFRACTION OF LIGHT BY PLANE SURFACES-Exercises
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  2. A slab of glass of refractive index 1.5 and thickness 3cm is placed wi...

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  3. A microscope is focused on a mark on a piece of paper and then a slab ...

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  4. A container is filled with water (mu=1.33) upto a height of 33.25 cm. ...

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  5. A diverging beam of light from a point source S having devergence angl...

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  6. A concave mirror is placed at the bottom of an empty tank with face up...

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  7. A pile driven into the bottom of a lake extends 3m above the bottom of...

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  8. A concave mirror with its optic axis vertical and mirror facinig upwar...

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  9. The mean distance of sun from the earth is 1.5xx10^8km. The time taken...

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  10. A ray of light composed of blue and red light is incident on a paralle...

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  11. When a ray of light enters a water filled glass tank from a glass face...

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  12. Light passes through a glass slab with parallel sides and thickness t....

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  13. A ray of light is incident on a surface of glass slab at an angle 45^@...

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  14. Two transparent slabs have the same thickness as shown in figure. One ...

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  15. A ray of light is incident on the surface of a glass plate of thicknes...

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  16. Maximum lateral displacement of ray light incident on a slab of thickn...

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  17. Two optical media of refractive indices n1 and n2 contain x and y wave...

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  18. Refractive index of air is 1.0003. The correct thickness of air column...

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  19. If hat(i) denotes a unit vector along incident light ray, hat (r)a uni...

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  20. The apparent depth of water in cylindrical water tank of diameter 2R c...

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