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A cylindrical hall of diameter D and hei...

A cylindrical hall of diameter D and height h is illuminated by a lamp fixed at the centre of the celing. Compare the minimum illumination of the froor.

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D/2h
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  8. An infinite number of lamps, each of luminous intensity 100 cd are pla...

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  9. At what height should a lamp be hung above the centre of a round table...

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  10. A cylindrical hall of diameter D and height h is illuminated by a lamp...

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  14. An electric lamp of 100 cd consumes 0.5 watt of electrical energy per ...

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  15. Find the average illuminance of the irradiated part of an opaque spher...

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  16. A luminious hemispherical dome rests on a horizontal plane. Find the i...

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  17. A lambert source has the from of an infinte plane. Its luminance is L....

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  18. Determine the luminosity of a surface whose luminance depends on direc...

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  19. Two light sources of luminous intensities P and 2P are placed 2 m apar...

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