Chapter 11, Problem 11RQ

To determine

Whether a magnetic force also acts on a current-carrying wire when the force acts on the moving charged particle.

Answer to Problem 11RQ

The direction of the magnetic force on a moving charge is always perpendicular to the magnetic field lines.

Explanation of Solution

Magnets have no effects on a charged particle, which is at rest. When at movements, these charged particles experience a deflecting force when exposed to magnets. This deflecting force is maximum when the particles move perpendicular to the magnetic field lines. At other angles, the force is less and becomes zero when the particle moves parallel to the lines.

The force always acts perpendicular to the magnetic field lines as well as the velocity of the charged particles.

Conclusion:

Therefore, the direction of the magnetic force on a moving charge is always perpendicular to the magnetic field lines.