1. The problem statement, all variables and given/known data A uniform magnetic field of magnitude 0.137 T is directed along the positive x axis. A positron moving at a speed of 5.40 106 m/s enters the field along a direction that makes an angle of θ = 85.0° with the x axis (see figure below). The motion of the particle is expected to be a helix. (a) Calculate the pitch p of the trajectory as defined in figure. (b) Calculate the radius r of the trajectory as defined in figure. 2. Relevant equations vx = sqrt(vy^2 + vz^2) R = (m (vx) )/ qB T = (2 pi r ) / vx 3. The attempt at a solution To find vx multiply v vector by sin(5 degrees). Plugging in values to radius. Answer is significantly wrong. To find pitch, p = (vx)T = 2 pi r.