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If for a lens , f= -20 cm, what is the p...

If for a lens , f= -20 cm, what is the power of the lens ?

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NAVNEET PUBLICATION-LENSES-EXERCISE
  1. Solve the following examples/ numerical problems: Calculate the foca...

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  2. Three lenses having power 2, 2.5 and 1.7 D are kept touching in a row....

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  3. Solve the following examples/ numerical problems: Two convex lenses ...

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  4. Solve the following examples/ numerical problems: Two convex lenses ...

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  5. Solve the following examples/ numerical problems: < br > If a convex l...

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  6. Find the focal length of a convex lens which produces a real image at ...

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  7. Find the focal length of a convex lens which produces a virtual image ...

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  8. A real image is obtained at 30 cm from a convex lens of focal length 7...

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  9. An object is kept at 20 cm in front of a convex lens its real image is...

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  10. An object is kept at 10 cm in front of a convex lens . Its image is f...

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  11. An object is kept at 60 cm in front of a convex lens of focal length 1...

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  12. An object of height 2 cm is kept at 30 cm from a convex lens . Its rea...

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  13. If the power of a lens is 4 dioptres , find its focal length.

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  14. Find the power of a convex lens of focal length 40 cm.

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  15. Find the power of a convex lens of focal length 12.5 cm.

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  16. If for a lens , f= -20 cm, what is the power of the lens ?

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  17. An object of height 4 cm is kept in front of a concave lens of focal l...

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  18. If two convex lenses of focal lengths 10 cm and 5 cm are kept in conta...

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  19. If a convex lens of focal length 20 cm and a concave lens of focal len...

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  20. If a concave lens of focal length 12 cm and a convex lens of focal len...

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