A particle travels in a region containing a uniform magnetic field and a parallel, uniform electric field. At a specific instant, the particle's velocity is perpendicular to the direction of the fields. The path taken by the particle will be

Step-by-step solution

Let the uniform electric and magnetic fields be directed along the z-axis, so E = E k and B = B k . The initial velocity of the particle is perpendicular to the fields. Let v = v₀ i . The magnetic force acting on the particle is F _m = q( v B ) , which provides the necessary centripetal force to move the particle in a circular path in the plane perpendicular to the magnetic field. The radius of this circular path is constant since the perpendicular speed remains constant. The electric force acting on the particle i