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Derive the lens formula, (1)/(f)=(1)/(v)...

Derive the lens formula, `(1)/(f)=(1)/(v)-(1)/(u)` for a concave lens, using the necessary ray diagram.
Two lenses of powers 10 D and -5 D are placed in contact.
(i) Calculate the power of the new lens.
(ii) Where should an object be held from the lens, so as to obtain a virtual image of magnification 2?

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RESONANCE ENGLISH-GEOMATRICAL OPTICS -Exercise-3
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  2. (a) For a ray of light travelling from a denser medium of refractive ...

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  3. Derive the lens formula, (1)/(f)=(1)/(v)-(1)/(u) for a concave lens, u...

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  4. A ray of light passing through an equilateral traingular glass prism f...

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  5. (a) Draw a ray diagram showing the passage of light through a glass pr...

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  6. A glass lens of refractive index 1.5 is placed in a trough of liquid....

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  7. (a) Draw the ray diagram for the formation of image of an object by a ...

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  8. Why are convex mirrors used as side view mirrors in cars ?

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  9. Three light rays red (R), green (G) and blue (B) are incident on a rig...

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  10. The far point of a myopic person is 80 cm in front of the eye. What is...

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  11. (a) (i) Draw a labelled ray diagram to show the formation of image in ...

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  12. (a) Draw the ray diagram showing the geometry of formation of the imag...

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  13. The image obtained with a convex lens is erect and its length is 4 tim...

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  14. A converging lens is kept coaxially in contact with a diverging lens -...

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  15. Draw a ray diagram to show the working of a compound microscope. Deduc...

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  16. An astronomical telescope has an objective of focal length 20 cm and a...

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  17. A convex lens made up of glass of refractive index 1.5 is dipped, in t...

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  18. Use the mirror equation to deduct that : (a) an object between f and...

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  19. A gaint refracting telescope at an observatory has an objective lens o...

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  20. A beam of light converges at a point P. Now a lens is placed in the pa...

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