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About 5% of the power of a 100W bulb is ...

About 5% of the power of a 100W bulb is converted to visible radiation. What is the average intensity of visible adiation.
At a distance 10m ?

Text Solution

Verified by Experts

Intensity at 10m distance and at `5% = 100/(4xx3.142 xx(10)^2) = 0.0796 Wm^(-2)`
At 5%, average intensity of radiation = `0.07896 xx 0.05 = 3.98 xx10^(-3) Wm^(-3)`.
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