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A lamp of luminous intensity 100 cd is h...

A lamp of luminous intensity 100 cd is held at a distance of 2 m from a vertical wall. A plane mirror is fixexd on the opposite wall which is at a distance of 4 m from the lamp. Calculate the illumainance on the wall opposite to the mirror at a point on the horizontal line through the lamp. Also calculate the luminous flux on a small area or `0.02 m^(2)` surrounding the point.

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The correct Answer is:
`26 lux, 0.52` lumen
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