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Black body radiation

  1. Jan 26, 2005 #1
    why can't classcial mechanic explain black body radiation?
  2. jcsd
  3. Jan 26, 2005 #2
  4. Jan 27, 2005 #3
    Because if you calculate the number of possible configurations as a function of the emitted wavelength and the temperature (the socalled Rayleigh-Jeans spectral distribution) you can use this quantity to calculate the emitted energy by integrating over the wavelengths. Now, (and here is the problem) if you calculate this energy and you insert very low values for lambda (ie if the wavelength evolves toward 0) you will get an infinetely large energy-value. This is NOT in correspondence with experimental data, because if lambda goes to ZERO, this energy should LOWER instead of rising. The solution was that the involved harmonic oscillators had to have discrete energy values in stead of any finite arbitrary value (as in classical physics).


    ps : this is how the constant of Planck was born
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