1. The problem statement, all variables and given/known data Light with wavelength 452 nm illuminates a surface. The work function of the surface is 5.77 electron volts. 1. What is the frequency of light hitting the surface? 2. What is the maximum kinetic energy of the electron ejected from this surface? 3. What backing voltage would need to be applied to stop all electrons ejected from this surface from reaching the anode? 3. The attempt at a solution 1) f = [itex]\phi[/itex]/h f = 5.77/(4.14*10^-15) = 1.39*10^15 Hz 2) K = (hc/[itex]\lambda[/itex]) - [itex]\phi[/itex] K = (4.14*10^-15*3*10^8)/(452*10^-9) - 5.77 = -3.02eV 3) I'm not too sure how to start 3. I'm fairly sure part 1 is correct, I didn't expect to get a negative value for part 2 so I'm sure that's not right, what did I do wrong?