1. The problem statement, all variables and given/known data Electron diffracation experiment show that the wavelength of a electron is 0.15nm. Find the momentum of the electron in the beam. ii) Through what the potential diffrenece should the electron accelerated from rest to acquire this momentum? 2. Relevant equations 3. The attempt at a solution λ= h/p , p=momentum = (6.63x10^-34) / 550x10^-9 = 4.42x10^-24kgm/s 1/2 mc2 = eV pc = 2eV V= pc/2e = (4.42X10^-24) ( 3x10^8) / (2 x 1.6x10^-19) = 4143 V but the ans is 67V .... why i am wrong?