a) A particle with charge q has a velocity of V = vxx^ +vyy^ and is in a region that has a magnetic field B = B_zz^. What is the force on this particle due to this external magnetic field.

b) A particle has a charge q and has a constant velocity in the x-direction. It is in a region with a constant magnetic field in the z-direction. Derive the angular frequency of the particle, the radius of the orbit, and the period of the orbit.