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An infinite number of lamps, each of lum...

An infinite number of lamps, each of luminous intensity 100 cd are placed 1 m apart in a horizontal line perpendicular to a wall. The nearest being 1 m from the wall. Calculate the illuminance at a point on the wall lying on the line through the lamps.
Given `sum_(1) =1//n^(2)=pi^(2)//6`

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The correct Answer is:
`164.5 lux`
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