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Find the emissive power from "0.3 cm"^(2...

Find the emissive power from `"0.3 cm"^(2)` surface of filament of bulb of tungsten at 3000 K temperature. Take `e=0.4` for tungsten bulb.

Text Solution

Verified by Experts

From Stefan - Boltzmaan law,
`H=AesigmaT^(4)`
`=0.3xx10^(-4)xx0.4xx5.67xx10^(-8)xx(3000)^(4)`
`=55.1124`
`:.` H `~~` 60 W (Acc. to textbook value)
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