Q.33 A uniform and constant magnetic field
exists in the 
direction in vacuum. A particle of mass m with a small charge q is introduced into this region with an initial velocity 
. Given that B, m, q ,
are all non-zero, which one of the following describes the eventual trajectory of the particle?
(A) Helical motion in the direction
(B) Circular motion in the xy plane
(C) Linear motion in the direction
(D) Linear motion in the 
direction
Answer: (A)
Explanation:
