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Spectral radiant exitance when given temperature

  1. Jan 25, 2013 #1
    1. The problem statement, all variables and given/known data

    Calculate the spectral radiant exitance for a 10um black body at the following temperatures: -12.0°C, 0°C, 12°C, 1600 K, and 2500 K

    Known:
    wavelength = 10um
    temperature = see above

    2. Relevant equations

    Planck's equation I think

    3. The attempt at a solution

    No idea. I can't figure out the equation (I am a major noob at this). The given equation is:

    Mλ = C1 / (λ5 [e(C2/λT) - 1)

    λ = wavelength in micrometres
    T = temperature in Kelvin

    C1 and C2 are supposed to be Planck's constants. What does the "e" mean?
     
  2. jcsd
  3. Jan 25, 2013 #2

    cepheid

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    WOW, okay, you are missing some fundamental math background here. Have you had a course in calculus yet?

    Try reading through these articles:

    http://en.wikipedia.org/wiki/E_(mathematical_constant)
    http://en.wikipedia.org/wiki/Exponential_function
     
  4. Jan 27, 2013 #3
    Nope, lol. It's for a geography class.

    I assume the e means 2.71828 then?
     
    Last edited by a moderator: Jan 27, 2013
  5. Jan 27, 2013 #4

    cepheid

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    Yeah. Did you read those articles (or at least the intros for each one)? The Planck function includes an exponential function (which is e to the power of some variable).
     
  6. Feb 1, 2013 #5
    I read the intros, yes. I think I just need an example of this equation done for me. The teacher of my class didn't really give us one.
     
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