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An optical (eye specialist)prescibes spe...

An optical (eye specialist)prescibes spetacles is a pateint with a combination of a convex lens of focal length 40 cm nd concave lens 25 cm.The power of spectacles is:

A

`6.5D`

B

`1.5 D`

C

`-6.67 D`

D

`-1.5 D`.

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MODERN PUBLICATION-UNIT TEST -06-EXERCISE
  1. Two lenses have powers + 1 D and - 2 D respectively ,The power of comb...

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  2. Two lenses having powers + 6 D and - 4D are placed in contact.The powe...

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  3. An optical (eye specialist)prescibes spetacles is a pateint with a com...

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  4. The focal length of a convex lens is 30 cm and the size of image is qu...

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  5. A screen is placed 80 cm from an object. The image of the object on th...

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  6. Which of the following pairs can produce erect,diminshed and virutual ...

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  7. In order to obtain a real image of magnification 2 using a convergin l...

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  8. Which of the following is true for rays coming from infinity?

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  9. At what angle ,a ray of light will incident on one face of an equilate...

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  10. The blue colour of the sky is due to the phenomenon of

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  11. The sky appears blue, because.

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  12. A red piece of paper when illuminated by green light appears:

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  13. White light is passed through a dilute solution of potasssium permagna...

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  14. C.V. Raman received Nobel Prize for the discovery of the following phe...

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  15. C.V. Raman received Nobel Prize for the discovery of the following phe...

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  16. The formation of rainbow in due to the phenomenon of

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  17. If red light and violet light rays are of focal length fr adn fv then ...

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  18. A parallel beam of white ligth falls on a convex lens .Images of blue...

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  19. The dispersive powers of the materials of the two lenses are in the r...

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  20. Retina of eye corresponds to which part of camera?

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