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A small lamp having the from of a unifro...

A small lamp having the from of a unifromly sphere of radius R=6 cm is suspended at a height h=3m above the floor. The luminance of the lampis equal to `L=2xx10^(4) cd//m^(2)`. Find the illuminance of the floor below the lamp.
(Hint:`P=sumLDeltaScostheta=LxxpiR^(2))`

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25 lux
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