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    I'm having a problem, the question is to derive the plank law as a function of the wavelength from the function originally as a function of the frequency

    the plank law as a function of frequency
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    the correct result as a function of wavelength
    Name:  plank.png
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    I cannot however get the result correct? Get the exponential bit right but not the part of the function

    any help?
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    Here's a hint, the functions each measure emission per unit frequency or wavelength, BUT a unit frequency is not a unit wavelength.

    What is true, however is that, 



\left| I(\nu)\ \!\mathrm{d}\nu\right|=|I( \lambda)\ \!\mathrm{d} \lambda| .
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    Oh of course, cheers, now got it correct
 
 
 
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