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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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Knowledge Check

  • Two lamps of luminous intensity of 8 Cd and 32 Cd respectively are lying at a distance of 1.2 m from each other. Where should a screen be placed between two lamps such that its two faces are equally illuminated due to two sources

    A
    10 cm from 8 Cd lamp
    B
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    40 cm from 8 Cd lamp
    D
    40 cm from 32 Cd lamp

  • Two light sources with equal luminous intensity are lying at a distance of 1.2 m from each other. Where should a screen be placed between them such that illuminance on one of its faces is four times that on another face

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