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If you lie on the ground at night with no cover, you get cold rather

 
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Nov23-12, 06:54 PM   #1
 

If you lie on the ground at night with no cover, you get cold rather


If you lie on the ground at night with no cover, you get cold rather quickly. Much of this is due to energy loss by radiation. At night in a dry climate, the temperature of the sky can drop to -40oC. If you are lying on the ground with thin clothing that provides little insulation, the surface temperature of your skin and clothes will be about 30 oC.


Estimate the net rate at which your body loses energy by radiation to the night sky under these conditions.


I know how to do the problem, but my issue is what area should I use? I have been using 1.8 m 2 but it's not working out.

Thank You!
 
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Nov23-12, 07:24 PM   #2
K^2
 
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I think, that's typical surface area of skin all around the body. Only half is exposed to night sky, though. So try half of that.
 
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