Why doesn't a charge repel a magnetic field in this example?

AI Thread Summary
An electron trapped in a magnetic field travels in a circular path, generating a magnetic field that circulates in the same direction as its motion. While a conductor would create an opposing magnetic field, the electron does not experience a similar repulsion due to the cancellation of forces from its own field. If the electron had a parallel velocity component, it would spiral instead of maintaining a circular path. The magnetic field around the electron reinforces on one side, allowing it to curve without net repulsion. Overall, the interaction of the electron's field with itself and the external magnetic field explains its behavior in this scenario.
Samson4
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The example:
An electron is trapped in a magnetic field. The electron travels along a circle in a clockwise path. It's my understanding that there is a magnetic field around the electron also circulating in a clockwise direction perpendicular to it's path. Now if this electron was in a conductor, the conductor would have a magnetic field opposing the original magnetic field. So, why doesn't the electron?

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Samson4 said:
The example:
An electron is trapped in a magnetic field. The electron travels along a circle in a clockwise path. It's my understanding that there is a magnetic field around the electron also circulating in a clockwise direction perpendicular to it's path. Now if this electron was in a conductor, the conductor would have a magnetic field opposing the original magnetic field. So, why doesn't the electron?

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Does not the electron perform a spiral as a result of what you are saying?
 
tech99 said:
Does not the electron perform a spiral as a result of what you are saying?
It will spiral if it has a parallel component to it's velocity.
 
Samson4 said:
The example:
An electron is trapped in a magnetic field. The electron travels along a circle in a clockwise path. It's my understanding that there is a magnetic field around the electron also circulating in a clockwise direction perpendicular to it's path. Now if this electron was in a conductor, the conductor would have a magnetic field opposing the original magnetic field. So, why doesn't the electron?

View attachment 111533
For the case of the loop of wire, the magnetic field inside the loop points in the opposite direction to that outside it. So overall, I don't think it has a force on it.
The single electron does seem to have a resultant force causing it to spiral, because it is acting like a loop edge-on to the magnetic field.
 
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tech99 said:
For the case of the loop of wire, the magnetic field inside the loop points in the opposite direction to that outside it. So overall, I don't think it has a force on it.
The single electron does seem to have a resultant force causing it to spiral, because it is acting like a loop edge-on to the magnetic field.
On my second point, I don't think I am correct here. The electron has opposite fields above and below it, so presumably these cancel.
 
Normally, you neglect the effect of a particle's field on itself. If you had more than one electron, then you would have to consider the effect of the electrons' fields on each other.
 
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I think the electron did work against its own field when it was accelerated to its present velocity and this energy is now mostly stored in its magnetic field.
 
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I see now that the magnetic field of the electron is reinforced on 1 side, according to the left hand rule. This makes since for the electron to curve away from that side without experiencing a net repulsion.
 
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