Net Power Transfer by Radiation

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ethanabaker1
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Homework Statement



A person with a skin temperature of 33 C and an emissivity of .9 is in a room at 24 C. What is the net power transfer by radiation. Let the area of the body be 1.8 m2.

Homework Equations


I=[itex]\frac{P}{A}[/itex]
[itex]\Delta[/itex]Irad=[itex]\epsilon[/itex][itex]\sigma[/itex]T4 (Stefan-Boltzmann Law)


The Attempt at a Solution


Temperature difference is 33-24=9 C
Irad=(.9)(5.67x10-8)(94)
Irad=3.34x10-4
IradA=Power
(3.34x10-4)(1.8)=6.03x10-4
 
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Well, power should have units of Watts. Emissivity has no units, and I know the Boltzmann constant is Wm-2K-4, so I wasn't sure if that means I should convert the temperature difference to Kelvin or not. I left it because both Kelvin and Celsius should have the same temperature difference. But I don't even know if that solution is reasonable.