Hello everyone! Our professor told us how to do this problem but it doesn't seem to be working. Here is what the problem says: (a) If the work function for a certain metal is 1.5 eV, what is its stopping potential for electrons ejected from the metal when light of wavelength 337 nm shines on the metal? Well he explained, the theory behind it, and it made sense. He then said, the Kenetic Engery (KE) will turn equal the Stopping Potential * electric charge of an electron. THe KE is in electron volts, eV. KE = (Stopping Potential)(Eelctric charge of electron); We want the stopping potential so: (stoppping Poential) = KE/1.602E-19; We find KE by the following: h = planks constant = 4.136E-15 eVs; KE = h*f - work; where f is the frequency; We find f by: f = c/wave length; f = (3E8 m/s)/(337E-9m) = 8.902E14 s^-1 they give us the work, so all we need now is to solve for KE, then we have to divide KE by charge of an electoron and that should be the answer. KE = (4.136E-15 eVs)( 8.902E14 s^-1) - 1.5eV; KE = 2.1819 eV; PE = 2.1819eV/1.602E-19; PE = 1.36196E19; Which is wrong. Someone got the answer right, but their answer was alot smaller tahn mine. They got 2.302 somthing, had no E19. Any ideas where i messed up? Thanks! they want the answer in Volts. I submitted 1.3619 omitting the E19, and also tried putting E19, both don't work.