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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 1 m from the bulb ?

Text Solution

Verified by Experts

Intensity at 1m distance = `("Power")/("Area") = 100/(4xx3.142 xx(t)^2), A = 4 pi r^2 = 7.957 Wm^(-2)`
At 5%, averge intensity of radiation = `7.957 xx 0.05 = 0.398 Wm^(-2)`
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