Chapter 8, Problem 44EAP

A charged particle of mass m moving with speed v in a plane perpendicular to a magnetic field experiences a force $\stackrel{\to }{F}$(qvB. perpendicular to $\stackrel{\to }{v}$ where q is the amount of charge and B is the magnetic field strength. Because the force is always perpendicular to the particle’s velocity, the particle undergoes uniform circular motion. Find an expression for the period of the motion. Gravity can be neglected.