Is Magnetic Force a Pseudo Force?

No, in the widely accepted framework of physics, magnetic force is generally not considered a pseudo force. It is a fundamental interaction arising from the relative motion of electric charges, a distinct component of the electromagnetic force.

Understanding Pseudo Forces

To clarify why magnetic force is typically not categorized as a pseudo force, it's essential to understand what pseudo forces are:

• Definition: A pseudo force (also known as an inertial force or fictitious force) is an apparent force that arises in a non-inertial (accelerating) reference frame. These forces do not result from any physical interaction between objects but are a consequence of the chosen reference frame's acceleration.
• Origin: They are introduced in Newton's second law ($F=ma$) to account for the observed acceleration of objects when applying the law in a non-inertial frame. Without them, Newton's laws would not hold in such frames.
• Examples: Common examples include the centrifugal force (an outward force experienced in a rotating frame) and the Coriolis force (an apparent deflection experienced by objects moving in a rotating frame).

The Nature of Magnetic Force

The magnetic force is a real, measurable force that describes the interaction between moving electric charges and magnetic fields.

• Lorentz Force: The fundamental equation describing this interaction is the Lorentz force law, given by $F = q(\mathbf{E} + \mathbf{v} \times \mathbf{B})$, where 'q' is the charge, 'E' is the electric field, 'v' is the velocity of the charge, and 'B' is the magnetic field. The term $q(\mathbf{v} \times \mathbf{B})$ represents the magnetic force.
• Relativistic Origin: Magnetic forces are intrinsically linked to electric forces through the principles of special relativity. What appears purely as an electric field in one inertial reference frame can appear as a combination of electric and magnetic fields in another inertial reference frame moving relative to the first. This is a key insight from Maxwell's equations and the theory of relativity.

Examining the Reference's Perspective

A specific viewpoint, as outlined in the provided reference from December 6, 2021, states:

"Magnetic force exist only if charge is moving, so it must be pseudo. Imagine, a positively charged man who has the same speed as electron (charge). So, he doesn't feel any magnetic force as charge is at rest with respect to him."

This perspective argues that because the magnetic force disappears or is absent when observed from a reference frame where the charge is at rest, it must be "pseudo." While it is true that magnetic force depends on the relative motion between the charge and the magnetic field (or the observer's frame), this characteristic does not align with the standard definition of a pseudo force.

Key Distinction:
The disappearance of a magnetic force in a specific inertial frame (where the charge is at rest) is a consequence of the relativistic nature of electromagnetism, where electric and magnetic phenomena are interchangeable aspects of the same underlying electromagnetic field. It means the force transforms into a purely electric force (or vanishes entirely if the only source is the charge itself), but it is still a real interaction that exists in other valid inertial frames. Pseudo forces, conversely, are entirely due to the observer's accelerating frame and would not be observed in an inertial frame.

Summary of Key Differences

The table below highlights the fundamental distinctions between pseudo forces and magnetic forces:

In conclusion, while the magnetic force's dependence on the observer's reference frame is a crucial aspect of its nature, this characteristic does not qualify it as a pseudo force under the standard scientific definition.