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

Question

Dr. Abubacker · Accepted Answer

(c) $I = \frac{L}{r^{2}} \Rightarrow \frac{L_{1}}{r_{1}^{2}} = \frac{L_{2}}{r_{2}^{2}}$
or $\frac{8}{x^{2}} = \frac{32}{(120 - x)^{2}}$
Solving it we get $x = 40\ cm$

Q. 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

Explanation

Reviewed by Dr. Abubacker

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