A particle that has mass m and charge q enters a uniform magnetic field that has magnitude B and is directed along the x axis. The initial velocity of the particle is in the xy plane.

a) Describe the particle's path as it travels through the magnetic field.

b) If the particle enters the magnetic field at t = 0, what is its angular displacement at t=2{eq}\pi {/eq}m/qB? Express your answer in terms of some or all of the variables m, q, B, and the constant {eq}\pi {/eq}?