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The overall luminous efficient of a 100 ...

The overall luminous efficient of a 100 W electric lamp is 25 lumen `W^-1`. Assume that light is emitted by the lamp only in the forward half, and is uniformly distributed in al diredctionsin this half. Calculate the luminous flux falling on a plane object of area `1cm^2` placed at a distance of 50 cm from the lamp and perpendicular to the line joining the lamp and the object.

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To solve the problem step by step, we will follow the outlined process in the video transcript, ensuring clarity and completeness. ### Step 1: Calculate the Total Luminous Flux from the Lamp Given: - Power of the lamp = 100 W - Luminous efficiency = 25 lumen/W The total luminous flux (Φ) emitted by the lamp can be calculated using the formula: ...
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