A charge q moving along the X-axis with a velocity v

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movingcharges

#1

A charge q moving along the X-axis with a velocity v is subjected to a uniform magnetic field B acting along the X-axis as it crosses the origin O.
(i)Trace trajectory.
(ii) Does the charged particle gain kinetic energy as it enters the magnetic field? Justify your answer.


#2

(i) As, the charged particle is moving perpendicularly to the magnetic field. So, it will perform circular motion in XY-plane.
(ii) No, the charged particle does not gain any KE as Lorentz force acting on it does not perform any work as ${ F }_{ m }$ perpendicular to v.