Fields and forces — definitions: Is “magnetic force” the correct term for the cause that produces a magnetic field, or is a magnetic field produced by electric currents and changing electric fields while magnetic force acts on charges in a field?

Introduction / Context:
Precise terminology matters. A magnetic field is produced by electric currents (moving charges) and changing electric fields; the field then exerts a magnetic force on moving charges or magnetic dipoles. Saying “magnetic force produces the magnetic field” reverses cause and effect and confuses core concepts of electromagnetism and Lorentz force.

Given Data / Assumptions:

• Classical electromagnetism framework.
• Moving charges and time-varying electric fields as sources of magnetic fields.
• Lorentz force law linking fields to forces on charges.

Concept / Approach:
Maxwell’s equations indicate that currents and changing electric fields create magnetic fields. The Lorentz force F on a charge q moving with velocity v in a magnetic field B is F = q * v × B (magnetic component). Thus, “magnetic force” is an effect of a pre-existing magnetic field acting on charges; it is not the agent that creates B. Permanent magnets produce fields due to atomic currents (electron spin/orbit) at the microscopic level—not because “force” is creating the field.

Step-by-Step Solution:

Verification / Alternative check:
In a straight wire with DC current, a circular B-field forms around the wire (right-hand rule). The force on a nearby test charge appears only because the B-field already exists due to current; turning off current removes the field and the magnetic component of force.

Why Other Options Are Wrong:
“Correct” misstates causality. Context qualifiers (permanent magnets, stationary charges, cryogenic temperatures) do not change the definitions.

Common Pitfalls:
Confusing “field sources” with “forces caused by fields.” Keeping these roles separate prevents conceptual errors in device analysis (motors, generators, magnetic storage).

Final Answer:
Incorrect