Answer
Rayleigh–Jeans law is a formula derived by Lord Rayleigh and Sir James Jeans in 1900. It describes the spectral radiance of black-body radiation at long wavelengths. The law states that the spectral radiance is proportional to the fourth power of the wavelength. However, the Rayleigh–Jeans law fails to accurately predict the spectral radiance at short wavelengths, where it overestimates the observed values.