F = Q(V×B)
For the electron passing through a magnetic field , the magnetic force acting will be given by
Fm = B e v sinθ(q=e)
(1) This force will be maximum when θ = 90 degree,such that
Fmax = B e v
(2) This force will be minimum when θ = 0 degree, 180 degree such that
Fmin = 0