Consider the motion of a positive point charge in a region where area simultaneous uniform electric and magnetic fields ` vec(E) = E_(0) hat(j)` and ` vec(B) = B_(0) hat(j)`. At time ` t = 0` , this charge has velocity ` vec(v)` in the ` x-y `plane , making an angle ` theta` with the ` x-axis `. Which of the following option(s) is (are) correct for time ` t gt 0`?

Options

A. If `theta=0^(@)`, the charge moves in a circular path in the x-z plane.
B. If `theta=0^(@)`, the charge undergoes helical motion with constant pitch along the y-axis.
C. If `theta=10^(@)`, the charge undergoes helical motion with its pitch increasing with time, along the y-axis.
D. If `theta=90^(@)`, the charge undergoes linear but acclerated motion along the y-axis.

Answer

C, D