The Rayleigh-Jean's Law describes the spectral radiance of electromagnetic radiation at all wavelengths from a black body at a given temperature through classical arguments. The Rayleign-Jeans law agrees with experimental results at large wavelengths but strongly disagrees at short wavelengths.
Think high wavelength, low frequency
For wavelength , it is:
For frequency , it is:
Recognizing the Rayleigh-Jean's TailEdit
We can simplify Plank's Law when the following inequality holds: