Does moving an insulating cylinder produce a magnetic field?

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Moving an insulating cylinder does not produce a magnetic field because the electrons are bound and cannot create a current. However, if there is charge in motion, it constitutes a current, which does generate a magnetic field. The discussion also touches on the behavior of dielectrics, noting that a moving polarized dielectric can produce a magnetic field, a concept explored by physicists like Röntgen and Eichenwald. This inquiry into the electrodynamics of moving bodies ultimately contributed to Einstein's theory of relativity. The relationship between charge motion and magnetic fields remains a fundamental aspect of electromagnetic theory.
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Suppose that we have an insulating cylinder with ##\rho_q##. If i move the cylinder towards ##+\hat{n}##, will it produce a magnetic field? My assumption is that since we have an insulator, then the electrons are bound and there cannot be a current, thus a magnetic field is not produced. Also, does this happen if we have a material full of dielectric?
 
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Assassinos said:
If i move the cylinder towards , will it produce a magnetic field? My assumption is that since we have an insulator, then the electrons are bound and there cannot be a current, thus a magnetic field is not produced.
If there is charge in motion then this is a current and there is a magnetic field.
Assassinos said:
Also, does this happen if we have a material full of dielectric?
I don't understand what you are asking here. What material is full of dielectric?
 
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Ibix said:
If there is charge in motion then this is a current and there is a magnetic field.

I don't understand what you are asking here. What material is full of dielectric?
Assume a sphere of radius R, and from 0 to R the sphere is filled with a dielectric of permittivity ε.
 
Is it charged and moving? If so, there's a current.
 
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Assassinos said:
My assumption is that since we have an insulator, then the electrons are bound and there cannot be a current
A moving charge density is a current: ##\vec j = \rho \vec v##
 
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One should add a comment to the question about the dielectric. That was a very hot question in the 19th century, where many physicists where very puzzled about the "electrodynamics of moving bodies", and it was indeed a question, what's the nature of polarization and if a moving polarized body would produce a magnetic field. This was investigated by Röntgen and Eichenwald, and confirmed that indeed a moving polarized dieelectric produces a magnetic field, which however only added on the puzzle about "electrodynamics of moving bodies".

The final solution of all these troubles was nothing less than Einstein's famous breakthrough paper in the Annalen der Physik titled modestly "On the electrodynamics of moving bodies" and lead to one of the "revolutions" in 20th-century physics, i.e., the (special) theory of relativity.
 
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