question_answer

A particle of charge q and mass m moving with a velocity v along the x-axis enters the region x > 0 with uniform magnetic field B along the \[\hat{k}\] direction. The particle will penetrate in this region in the x-direction upto a distance d equal to                                                   [MP PMT 1997]

A)            Zero                                         

B)            \[\frac{mv}{qB}\]

C)            \[\frac{2mv}{qB}\]            

D)            Infinity

Correct Answer: B

Solution :

                   It is easy to understand the given problem, along with the following figure. d = radius of path    \[=\frac{mv}{qB}\]