A charged particle moves with a constant speed through a region where a uniform magnetic field is present.If the magnetic field points straight upward,the magnetic force acting on this particle will be strongest when the particle moves
A)straight upward.
B)straight downward.
C)in a plane parallel to Earth's surface.
D)upward at an angle of 45° above the horizontal.

Question

Quizplus · Accepted Answer

The magnetic force on a charged particle is given by the equation F = qvBsinθ, where q is the magnitude of charge, v is the velocity, B is the magnetic field, and θ is the angle between the velocity of the particle and the direction of the magnetic field. Since the particle is moving with a constant speed, its velocity vector is always tangent to its path, and thus always parallel to the Earth's surface. Therefore, the angle θ between the velocity vector and the upward-pointing magnetic field is always 90°, which means sinθ is always 1. So, the magnetic force is strongest when the particle moves in a plane parallel to Earth's surface.

A Charged Particle Moves with a Constant Speed Through a Region