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andrew410
Oct25-04, 01:05 PM
At high noon, the Sun delivers 1,000 W to each square meter of a blacktop road. If the hot asphalt loses energy only by radiation, what is its equilibrium temperature?

I know the formula for energy rate of radiation:
P = \sigma A e T^4
I don't know how to apply this to the problem...
Any help would be great! Thx in advance ! :)

Tide
Oct25-04, 01:17 PM
If the blacktop is in thermal or radiative equilibrium it radiates the same amount of energy it absorbs.

andrew410
Oct25-04, 02:58 PM
So do I solve for T for the above formula and plug in the values? If so, then what is the emissivity(e)?

Tide
Oct25-04, 03:57 PM
e = 1 for an ideal radiator.

andrew410
Oct25-04, 04:01 PM
thanks a lot!!! :)