A particle of mass `m`and charge `q`, moving with velocity `v` enters Region `II` normal to the boundary as shown in the figure. Region `II` has a uniform magnetic field `B` perpendicular to the plane of the paper . The length of the region `II` is `l`. Choose the correct choice(s).

Options

A. The particle enters Region III only if its velocity `vgt(q1B)/(m)`
B. The particle enters Region III only if its velocity `vlt(q1B)/(m)`
C. Path length of the particle in Region II is maximum when velocity v = qlB / m
D. Time spent in Region II is same for any velocity v as long as the particle returns to Region I.

Answer

A, C, D