B Magnetic field produced by an electric current

[arivel]

Hi everyone .
if an alternating electric current passes through a piece of straight conducting wire, a proportional magnetic field appears on the orthogonal plane.
what happens to the magnetic field if instead of copper, as a conductor, I use different materials with particular characteristics?. I'm interested in knowing if the intensity of the field increases or stays that way.
let's take graphene as an example, in this material the speed of the electrons is much higher.
Thank you .

 

[Baluncore]

The external magnetic field is dependent on the flow of current, not on the nature of the conductive material.

The conductive material determines the efficiency of the electrical circuit that sources and maintains the current. The material may influence the current distribution, within a bulky conductor. That may slightly change the field when compared to a filamentary current.

 

[Dale]

In particular, if you have a given current density it produces the same magnetic field regardless of whether that represents a large charge density moving slowly or a small charge density moving quickly.

 

[arivel]

so if I understand correctly it depends only on the total number of electric charges in motion?

 

[Ibix]

so if I understand correctly it depends only on the total number of electric charges in motion?

As long as by "number in motion" you mean "number passing a point per unit time", yes. This can be achieved with different numbers of mobile electrons moving with different speeds.

So if you set up some current then switch materials and adjust your power source to get the same current the magnetic field will be the same as will the number of electrons passing any point, but the total number of electrons in motion and their speeds may be different.

 

[Baluncore]

One electron has a negative charge of 1.602×10⁻¹⁹ coulomb.
So it takes 6.2415×10¹⁸ electrons to make one coulomb of charge.
When one coulomb of charge flows past in one second, the current is one ampere.
The magnetic field is proportional to the current.