1. The problem statement, all variables and given/known data A positively charged particle of mass 7.2 * 10^-8kg is travelling east with speed of 85 m/s. The particle enters a 0.31 T uniform magnetic field, and 2.2 * 10^-3 secounds later leaves the field one-quarter south with speed of 85 m/s. What is the charge of the particle and magnetic force? 2. Relevant equations Fc=Fm mv^2/r=qvB Fm=qvB 3. The attempt at a solution I tried but I don't have radius and charge what do I do?