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Answer the following questions: (b) A ...

Answer the following questions:
(b) A virtual image, we always say, cannot be caught on a screen. Yet when we 'see' a virtual image, we are obviously bringing it on to the 'screen' (i.e., the retina) of our eye. Is there a contradiction?

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(b) When the reflected or refracted rays are divergent, the image is virtual. The divergent rays can be converged on to a screen by means of an appropriate converging lens. The convex lens of the eye does just that. The virtual image here serves as an object for the lens to produce a real image. Note, the screen here is not located at the position of the virtual image. There is no contradiction.
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NCERT GUJARATI-RAY OPTICS AND OPTICAL INSTRUMENTS-EXERCISES
  1. (a) Figure 9.32 shows a cross-section of a 'light pipe' made of a glas...

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  2. Answer the following questions: (a) You have learnt that plane and c...

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  3. Answer the following questions: (b) A virtual image, we always say, ...

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  4. Answer the following questions: (c) A diver under water, looks obliq...

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  5. Answer the following questions: (d) Does the apparent depth of a tan...

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  6. Answer the following questions: (e) The refractive index of diamond ...

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  7. The image of a small electric bulb fixed on the wall of a room is to b...

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  8. A screen is placed 90cm from an object. The image of the object on the...

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  9. (a) Determine the 'effective focal length' of the combination of the t...

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  10. At what angle should a ray of light be incident on the face of a prism...

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  11. A card sheet divided into squares each of size 1 mm^(2) is being viewe...

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  12. (a) At what distance should the lens be held from the figure in Exerci...

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  13. What should be the distance between the object in Exercise 9.24 and th...

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  14. Answer the following questions: (a) The angle subtended at the eye b...

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  15. Answer the following questions: (b) In viewing through a magnifying ...

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  16. Answer the following questions: (c) Magnifying power of a simple mic...

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  17. Answer the following questions: (d) Why must both the objective and ...

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  18. Answer the following questions: (e) When viewing through a compound ...

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  19. An angular magnification (magnifying power) of 30X is desired using an...

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  20. A small telescope has an objective lens of focal length 140cm and an e...

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