1. The problem statement, all variables and given/known data I have another question, An incandescent light bulb consuming 75 W emits only 5% of this energy as visible light of wavelength 597 nm; the frequency of the emitted light is 5.02e+14 Hz. How many photons per second of this light does the bulb emit? 2. Relevant equations E = hf 3. The attempt at a solution E = (6.626068e-34)x(5.02513e14 Hz)= 3.3297e-28 J/photon 75 W = 75 J/s (75 J/s)/(3.3297e-28 J/photon) = 2.252e29 photon/s but.... I'm wrong... I don't know why.