1. The problem statement, all variables and given/known data A proton is accelerated from a rest position into a uniform electric field and magnetic field that are perpindicular to each other, as shown, The proton passes through the parralel plates without being deflected, at a constant velocity. When the proton leaves the plates, it only experiences a magnetic force. The magnitude of the electric field is 1.2 x 10^4 n/c and the magnetic field is 0.20T. a) Find the speed of the proton. b) Find the radius of the path of the proton as it leaves the plates. 2. Relevant equations FM = qvB FE = Eq Fc = (mv^2)/r 3. The attempt at a solution a) Fnet = FM + FE 0 = FM - FE FM = FE qvB = Eq v = E/B = (1.2 x 10^4 N/C) / (0.20 T) = 6.0 x 10^4 m/s b) FM = FC qvB = mv^2/r qB = mv/r r = mv/qB = (1.67e-27 kg)(6.0e4 m/s)/(1.60e-19 C)(0.20T) = 3.1 x 10^-3 m I'm not certain how to think about this situation since the velocity associated with magnetic force is perpendicular to the force.