Effect of the magnetic field on a charged object's inertia.

AI Thread Summary
The discussion explores the relationship between a charged object's inertia and its interaction with magnetic fields. It questions whether the energy stored in the magnetic field of a moving electron affects its final velocity, suggesting that this could imply a difference between inertia mass and gravitational mass. Participants clarify that while magnetic fields do not change the object's inertia, they can influence kinetic energy. The conversation also touches on historical perspectives regarding the energy required to accelerate charged versus uncharged particles and the concept of effective mass in semiconductor physics. Overall, the inquiry highlights the complexities of electromagnetic interactions and their implications for particle dynamics.
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A question many of us repeatedly solved in high school goes like this: An electron is accellerated a certain distance by an electric field of a certain strength. Determine its final velocity.

I and my teachers always treated this as a simple F=ma question, but recently it's occurred to me that a moving charge has a magnetic field, and magnetic fields store energy. Does that mean the electron would end up moving more slowly because some of the energy that goes into the electron goes into the magnetic field? Does this mean the electron has an "inertia" mass higher than its "gravity charge" mass?
 
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You are saying that some of the energy that may otherwise have gone into the motion of the charge gets stored in it's magnetic field?

This does not change the inertia of the object though, just it's kinetic energy.
Have a go working out how big the effect is.
 
I don't believe that magnetic field of a single particle can store energy. I think you are referring to the effect of induction, which is different.
 
Of course in the semi-classical model of transport in a semiconductor, an electron is treated as having an effective mass different from it's rest mass.
 
It may be shown from the equations of electromagnetism, by James Clerk Maxwell in the 1860’s, that the speed of light in the vacuum of free space is related to electric permittivity (ϵ) and magnetic permeability (μ) by the equation: c=1/√( μ ϵ ) . This value is a constant for the vacuum of free space and is independent of the motion of the observer. It was this fact, in part, that led Albert Einstein to Special Relativity.

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