In a uniform magnetic field, a charged particle enters with a velocity component parallel to the magnetic field lines and another component perpendicular to them. What is the resulting trajectory of the particle?

💡 Solution & Explanation

When a charged particle has a velocity vector with both parallel and perpendicular components relative to a uniform magnetic field, the perpendicular component causes uniform circular motion while the parallel component remains unaffected, resulting in a helical trajectory. A purely perpendicular entry produces a circle, whereas a purely parallel entry results in a straight line. The radius of the helical path depends directly on the particle mass and perpendicular velocity, and inversely on its charge and magnetic field strength.