12.9 Forms of the Distribution Function f(λ)

From purely thermodynamic reasoning, Wien arrived at the relation


eλ, = λ −5f(λT)


where eλ is the monochromatic emissive power of a black body within the wavelength range λ to λ + dλ and at absolute temperature T.

12.9.1 Wien's Formula

Wien arrived at the following relation




on certain arbitrary assumptions; these assumptions are as follows:

  1. The radiation was produced by oscillators of atomic dimensions.
  2. The frequency of the emitted waves was proportional to the kinetic energy of the oscillators.
  3. The intensity in any particular wavelength range was proportional to the number of oscillators ...

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