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Two thin lenses with focal lenghts f(1) ...

Two thin lenses with focal lenghts `f_(1) and f_(2)` make a lens of focal length f given by

A

`f = f_1 + f_2`

B

`frac(1)(f) = frac(1)(f_1) + frac(1)(f_2)`

C

`f = frac(f_1)(f_2)`

D

`f = frac(f_2)(f_1)`

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TARGET PUBLICATION-OPTICS-EXERCISE
  1. A single lens, which will form the image of a given object at the same...

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  2. Two thin lenses may be combined so as to

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  3. Two thin lenses with focal lenghts f(1) and f(2) make a lens of focal ...

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  4. Two thin converging lenses of focal length 15 cm and 30 cm are held i...

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  5. What is the focal of the combination of a convex lens of focal length...

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  6. Two thin lenses, aone convex of focal length 10 cm and other concave l...

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  7. Two lenses of power +12and-2 dioptres are placed in contact. What will...

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  8. When two or more lnses of magnification m(1) ,m(2), m(3) are kept in c...

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  9. The separation of whtie light into its constituent colours after passi...

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  10. A shaped triangular transparent block havin three rectangular planes ...

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  11. The angle between the two-plane rectangular refracing surface of a pri...

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  12. The rectangular face opposite to the refracting edge is called .

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  13. The refractivity of the material of the prism is given by

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  14. A glass prism placed in a homogeneous transparent medium will deviate ...

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  15. As the refractive index of the material of prism for different colours...

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  16. When while light passes through prism then constituent colours are obt...

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  17. A prism splits a beam of white light into its constituent colours. Thi...

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  18. Dispersion of light is shown in the following diagram, select the CORR...

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  19. The angle between incident ray and ray is called angle of deviation.

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  20. When white light passes through prism, the angle of deviation is

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