Which term describes the force that causes a moving electric charge to deviate when it passes through a magnetic field?

Which term describes the force that causes a moving electric charge to deviate when it passes through a magnetic field?

• A. Lorentz force
• B. Inertial force
• C. Deflecting force
• D. Centripetal force

Answer: (C)

The force responsible for bending a moving charge in a magnetic field is the Lorentz force. It’s described by F = q(v × B), so the force is always perpendicular to both the velocity and the magnetic field. That perpendicular orientation means the force changes the direction of motion without doing work on the charge, so the speed stays the same while the path curves. If the velocity is entirely perpendicular to the field, this force provides the centripetal acceleration that makes the particle trace a circle with radius r = mv/(qB). If there’s a component of velocity along the field, the motion becomes helical, combining circular motion around field lines with forward motion along them. While the motion can be described as a deflection, the standard term for the force causing it is the Lorentz force. Deflecting force isn’t a formal name for this interaction.

The force responsible for bending a moving charge in a magnetic field is the Lorentz force. It’s described by F = q(v × B), so the force is always perpendicular to both the velocity and the magnetic field. That perpendicular orientation means the force changes the direction of motion without doing work on the charge, so the speed stays the same while the path curves.

If the velocity is entirely perpendicular to the field, this force provides the centripetal acceleration that makes the particle trace a circle with radius r = mv/(qB). If there’s a component of velocity along the field, the motion becomes helical, combining circular motion around field lines with forward motion along them.

While the motion can be described as a deflection, the standard term for the force causing it is the Lorentz force. Deflecting force isn’t a formal name for this interaction.