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Assertion :- The twinkling of stars is d...

Assertion :- The twinkling of stars is due to the fact that refractive index of the earth's atmosphere fluctuates.
Reason :- In cold countries, the phenomenon of looming (i.e ship appears in the sky) takes place, because refractive index of air decreases with height.

A

If both Assertion & Reason are True & Reason is a correct explanation of the Assertion.

B

If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.

C

If Assertion is True but the Reason is False.

D

If both Assertion & Reason are False.

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The correct Answer is:
B
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MOTION-RAY OPTICS-Exercise-4
  1. Assertion : A star will appear to twink le if seen from free spa...

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  2. Assertion : A beam of white light when passed through a hollow ...

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  3. Assertion :- The twinkling of stars is due to the fact that refractive...

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  4. Assertion :- Critical angle is maximum for red colour in water-air sy...

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  5. Assertion :- The minimum distance between a real object and its real i...

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  6. Assertion :- Chromatic aberration occur in simple lenses but not in mi...

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  7. Assertion : In a compound microscope, the intermediate image is real, ...

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  8. Assertion :- 11 english alphabets donot show lateral inversion. Rea...

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  9. Assertion :- Sky appears blue. Reason :- Sensitivity of eye is high...

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  10. Assertion : The images formed by total internal reflections are much b...

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  11. Assertion : The focal length of lens does not change when red light is...

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  12. Assertion : By roughening the surface of a glass sheet its transparenc...

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  13. Assertion : Diamond glitters brilliantly. Reason : Diamond does not ...

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  14. Assertion : The resolving power of a telescope is more if the diameter...

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  15. Assertion : In optical fibre, the diameter of the core is kept small. ...

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  16. Assertion:- In modem microspore multicomponent lenses are used for bot...

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  17. Assertion:- A man inside the water see a tree, the tree will appear l...

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  18. Assertion:- Clouds are white. Reason:- Scattering of all colours are...

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  19. Assertion:- When a white light is passed through a lens, Violet light...

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  20. Assertion:- Microscope magnifies the image. Reason:- Angular magnifi...

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