Question

A charged particle is injected into a uniform magnetic field such that its velocity vector is perpendicular to the magnetic field vector. ignoring the particle's weight, the particle will
a.move in a straight line
b.follow a spiral path
c.move along a parabolic path
d.follow a circular path

Answer 1

Magnetic forces can cause charged particlesto move in circular or spiral paths. Particleaccelerators keep protons following circular paths with magnetic force. ... The magnetic force is perpendicular to the velocity, and so velocity changes in direction but not magnitude. Uniform circular motion results

Answer 2

The particle injected into a uniform magnetic field with its velocity vector perpendicular to the magnetic field will follow a circular path.

• The only force acting on the particle will be the magnetic force which is given by q(v×B).
• The magnetic force is the cross product of velocity and magnetic field vector, so it will be directed perpendicular to both velocity as well as magnetic field vector.
• Since, the force is perpendicular to the velocity, the particle will follow a circular path.