The electron accelerator uses a potential difference to speed up electrons from rest and inject them into the magnetic field of the Helmholtz coil. Use the Work-Energy Theorem to derive an equation for the speed of the electron as it enters the field of the Helmholtz coil in terms of this potential difference. Use Newton's 2 Law to derive an equation for the radius of the uniform circular motion of the electrons once they are in the magnetic field in terms of the magnetic field, the speed of the electrons, their charge and their mass. Using the previous two equations and the given equation of the magnetic field of the Helmholtz coil, derive an equation that relates the radius of the circular path to the current in the Helmholtz coil. Given the equation you developed in the previous question, propose a linear graph you could make in Excel or Logger Pro that would allow you to find the value of em for an electron.