m: mass. V: velocity (vector) B: magnetic field.
e: charge. eta: friction coefficient. r(t): position of
the particle at time t, vector
Then:
m dV/dt=eV X B (X:cross product)-eta V
integrate the above equation with dt from t=0 to t=infinitym
m (V(t=infinity)-V(t=0))=e r(t=infinity) X B - eta
r(t=infinity).
=-m V(t=0)
you can solve this algebric equation to get
r(t=infinity) easily.
