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Calculate the power of an incandescent l...

Calculate the power of an incandescent lamp whose filament has a surface area of `0.19 cm^(2)` and is at a temperature of 3645K. Emmisivity of the surface is 0.4, `sigma = 5.7xx10^(-8)Wm^(-2)K^(-4)` ?

Text Solution

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The correct Answer is:
80.49 Watt
`Q=esigmaT^(4)A=0.4xx5.7xx10^(-8)xx(3645)^(4)xx0.19xx10^(-4)=80.49` W
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