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About 5% of the power of a 100 W light b...

About 5% of the power of a 100 W light bulb is connected to visible radiation .what is the average intensity of visible radiation at the distance of 1 m from the bulb?

Text Solution

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Formula :
Intensity, I = `("Power of visible light")/("Area")`
I = `((5)/(100) xx 100 )/(4pi (l)^(2)) = 0.4 W//m^(2)`
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