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Homework Help: Simple Black Body Radiation Question

  1. May 14, 2009 #1
    1. The problem statement, all variables and given/known data
    The total radiation emitted by a certain star is a factor 16 times that of a second star of equal size. Calculate the ratio between the temperatures of the star.

    2. Relevant equations
    lamda x T = 2.90x10^-3

    3. The attempt at a solution
    16I = I

    Therefore, Wiens Displacement law (above):
    16I x T1 = I x T2
    Where I is equal on both sides.

    T2/T1 = 16
    I'm not too sure on what equations to apply to this! Do I use just Wien's Displacement Law and put them together? Doesn't look right (not supplied with answers).
    Or do I use the Stefan Boltzmann Law (I = oT^4)?

    How do I know which law to use?
    Any help is greatful!
  2. jcsd
  3. May 14, 2009 #2


    User Avatar
    Science Advisor

    Just look for the definitions of the Wien's Displacement Law and the Stefan-Boltzmann Law. What are they measuring? What are I, λ and T?
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