Net Power Transfer by Radiation

[ethanabaker1]

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=\frac{P}{A}
\DeltaI_rad=\epsilon\sigmaT⁴ (Stefan-Boltzman Law)

The Attempt at a Solution

Temperature difference is 33-24=9 C
I_rad=(.9)(5.67x10^-8)(9⁴)
I_rad=3.34x10^-4
I_radA=Power
(3.34x10^-4)(1.8)=6.03x10^-4

 

[SteamKing]

It probably would be nice to show a few more units in your calculations.

 

[ethanabaker1]

Well, power should have units of Watts. Emissivity has no units, and I know the Boltzman 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.