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A source emits 31.4 W of radiant flux di...

A source emits 31.4 W of radiant flux distributed uniformly in all directions. The luminous efficiency is 60 lumen watt. What is the luminous intensity of the source ?

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The correct Answer is:
A, C, D
Radiant flux `=31.4W, solid angle =4pi` Luminous efficiency =60 lumne/W So, Luminous flux =`60xx31.4` lumen and luminous intensity
`=(Luminous Flux)/(4pi)`
`=(60xx(31.4))/(4pi)`
`=150 candela`
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