A change particule is projected with velocity `v_(0)` at positive x-axis .The magnetic field B is direction s negative z-aixs between `x=0` and `x=l` . The particule emerges out (at x =L) at an angle of `60^(@)` with direction of projected (at x = 0) a positive x-axis so that wahen it emerges out (at x = L) the angle made by it is `30^(@)` with the direction projection

Options

A. `2v_(0)`
B. `v_(0)//2`
C. `v_(0)//sqrt(3)`
D. `v_(0)sqrt(3)`

Answer

D