I was reading about the photoelectric effect and it described that in the classical description of light, the changing of wavelength would effect the rate at which electrons were emitted. This theory was later proved wrong when Einstein introduced the idea of photons. However this theory goes on to say that the energy of a photon is inversely proportional to its wavelength, and therefore the wavelength does effect the rate at which electrons are emitted from metals. I'm confused to why wavelength can be used in both theories of the photoelectric effect. Please explain! thank you!