1. The problem statement, all variables and given/known data In a purley magnetic field B, motion of particle in x-y plane is circle; use this property, with result from part c to show on average the particle travels with constant velocity U: (answer given): U=(1/B^2)*B*(B*Vo)+Vdrift where Vdrift=(1/B^2)(ExB) 2. Relevant equations "x" implies cross product E=0i+Ej+0k B=0i+0j+Bk F=q(E+VxB) results from Part c) showed by Galilei transform: E'=(E+UxB) V'=(V-U) 3. The attempt at a solution Well right now i'm solving for U. I also have the answer so i've plugged in vdrift and try to work that out, usually "show" means working backwards in this course. I am not sure if I should use trig functions for the circle, I mean, it says to use that property of pure magnetic feild, I know at one point i have to incorporate the trig rotation because in part f it says my x(t) and y(t) are sin and cos functions.