1. The problem statement, all variables and given/known data This is a problem I did during a test, and I am looking it over to see what I did wrong.. 1. An Electron is accelerated by a potential difference of 75V. What is the de Broglie wavelength 2. Relevant equations P = h/λ Ek = 1/2mv^2 eV = 1.6E-19 3. The attempt at a solution P = h/λ λ = h/p (1) Ek = 1/2mv^2 (2Ek/m)^1/2 (2) Sub (1) into (2) λ = h/p λ = h/m((2Ek/m)^1/2) I figured 75V = 75*eV = 75*(1.6E-19) = 1.2E-17J So 1.2E-17J = Ek I Plugged in all the known values into λ = h/m((2Ek/m)^1/2) and got the answer as: 1.4E21 Any clues as to what I did wrong? I assume it has something to do with my volt conversion, any help would be greatly appreciated.