1. The problem statement, all variables and given/known data Photoelectric experiment show that about 5eV of energy are required to remove an electron from platinum, if light of 150nm wavelength is used, what is the velocity of the emitted electron? 2. Relevant equations de broglie's equation, E=hv 3. The attempt at a solution Tried by using the de Broglie's equation, to find the velocity but wasn't successful.