1. The problem statement, all variables and given/known data What is the length of a one-dimensional box in which an electron in the n=1 state has the same energy as a photon with a wavelength of 500 nm 2. Relevant equations E=h^2/8mL^2 and E=hc/lambda making it L=sqrt( (h*lambda)/(8cm) ) 3. The attempt at a solution I plugged in for those numbers and did not come out with the correct number. any suggestions?