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Homework Help: Need help on Radiation

  1. Oct 25, 2004 #1
    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:
    [tex] P = \sigma A e T^4 [/tex]
    I don't know how to apply this to the problem...
    Any help would be great! Thx in advance ! :)
     
  2. jcsd
  3. Oct 25, 2004 #2

    Tide

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    If the blacktop is in thermal or radiative equilibrium it radiates the same amount of energy it absorbs.
     
  4. Oct 25, 2004 #3
    So do I solve for T for the above formula and plug in the values? If so, then what is the emissivity(e)?
     
  5. Oct 25, 2004 #4

    Tide

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    e = 1 for an ideal radiator.
     
  6. Oct 25, 2004 #5
    thanks a lot!!! :)
     
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