1. The problem statement, all variables and given/known data In Problem 1 find the number density of photons in the sun’s core for the region of wavelengths between 599 nm and 601 nm. In problem 1 temperature is given. 2. Relevant equations Planck blackbody formula and number density= constant times T^3 where T is temperature. 3. The attempt at a solution Everyone is telling me to use the constant times T^3 formula but that makes no sense in this problem. The constant times T^3 is only when all frequencies are integrated. However only a slice of frequency is considered. Is this question an error or something. A lot of questions and slides had errors in this class so far.