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At what distance form a light source of ...

At what distance form a light source of 64 cd, will the intensity of illumination because 4 flux ?

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4m
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SL ARORA-RAY OPTICS-Problems For Self Practice
  1. Iluminance of 2.4 xx 10^(5)lm//m^(2) of the surface is produced by sun...

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  2. The luminous effeciency of a lamp is 51mW^(-1) and its luminous intens...

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  3. At what distance form a light source of 64 cd, will the intensity of i...

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  4. Calculate the illuminance at a surface distance 0.5m from a ligth sour...

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  5. A good photographic print is obtained by an exposure of 2s at a distan...

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  6. Two lamps of illuminating powers 25 cd and 100 cd are placed at the en...

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  7. Two light sources of intensities 8 cd and 12 cd are placed on the same...

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  8. A lamp is hanging at a height of 4 m above a table. The lamp is lowere...

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  9. In Bunsen's grease spot photometer, light from a lamp with dirty chimn...

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  10. An electric bulb illuminates a plane surface. The intensity of illumin...

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  11. A lamp is hanging along the axis of a circular table of radius r. at w...

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  12. An electric bulb is hanging above the centre of a circular table of ra...

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  13. In Fig. the circular cross-section of tunnel is shown. A 100 W almp is...

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  14. A frosted bulb which may be taken as an isotropic source, gives as ill...

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  15. A man is running away from a plane mirror at the speed of 5 ms^(-1). W...

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  16. A plane mirror rotating at an angular velocity of 3 radian/s reflects ...

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  17. A ray of light is incident at an angle of 60^(@) on a horizontal plane...

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  18. rays of light strike a horizontal plane mirror at an angle of 45^(@). ...

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  19. Two plane mirrors are inclined at angle theta as shown in figure. If a...

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  20. An object 0.04 m high is placed at a distance of 0.8 m from a concave ...

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