Hi there. So I had this lab last week about De Broglie hypothesis. In a simulation, we plugged in the electron velocity and the computer gave back a beautiful wavefunction, from wich I can measure the wavelength. So here I have an electron going at 0.6 m/s with a wavelenght of 0.00060606 meters. When we calculate the momentum, we have two choices, either p=mv or p=h/λ. I respectively found 5.466E^(-31) and 1.093291E^(-30). The link ? A factor of 1/2 between the two values. I did this with many other wavelengths and velocities. What is the point I am missing ? Shouldn't the two equations give the same answers ?