1. The problem statement, all variables and given/known data I(λ, T) is 4 pieces multiplied: (8π/λ4) (hc/λ) (1/(ehc/λkT-1) (c/4). 1. Identify the meaning of each term. 2. Which term(s) fix the ultraviolet catastrophe? 3. The attempt at a solution Well I know that the energy of a photon is given by (hc/λ), and I'm fairly certain it was Planck who introduced the ehc/λkT-1 term to reconcile the ultraviolet catastrophe, but that's about it. I've been looking through Planck's derivation and I am quite overwhelmed by the statistical analysis required.