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Offline thebrain13

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another electromagnetism question
« on: 19/09/2007 01:39:59 »
if you had two positively charged rings, and they were rotating next to each other on a plane side by side, one rotating clockwise and one rotating counter clockwise, would they experience magnetic repulsion?


 

Offline lightarrow

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another electromagnetism question
« Reply #1 on: 19/09/2007 11:40:34 »
if you had two positively charged rings, and they were rotating next to each other on a plane side by side, one rotating clockwise and one rotating counter clockwise, would they experience magnetic repulsion?
Yes.
 

Offline Soul Surfer

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another electromagnetism question
« Reply #2 on: 19/09/2007 13:53:52 »
They would experience electrostatic repulsion because both disks have positive charges but assuming that the charges do not move ie the disks are insulators the moving charges would be lelectrical currents circulating in opoposite directions and the magnetic forces generated by these currents would be attractive but in general these would not override the electrostatic repulsion. I do not think that rotating the disks very fast would allow the magnetic attraction to overcome the electrostatic repulsion but have not checked this out
 

Offline lightarrow

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another electromagnetism question
« Reply #3 on: 19/09/2007 15:39:33 »
Right; I imagined the two rings one over the other, but I should have read better. :(
 

Offline syhprum

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another electromagnetism question
« Reply #4 on: 19/09/2007 19:50:29 »
Please clear up a point for me, if the rings are conductive and bear a charge (an excess or deficit of electrons) does rotating them have the same effect as passing a current around them or does there have to be a dipole field.
« Last Edit: 19/09/2007 20:04:49 by syhprum »
 

Offline lightarrow

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another electromagnetism question
« Reply #5 on: 19/09/2007 21:44:45 »
Please clear up a point for me, if the rings are conductive and bear a charge (an excess or deficit of electrons) does rotating them have the same effect as passing a current around them or does there have to be a dipole field.
Concerning magnetic field it has the same effect, but concerning electric field obviously no because there is a net charge and so a net electric field (which is not a dipole field since there are only positive charges).
 

Offline syhprum

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another electromagnetism question
« Reply #6 on: 20/09/2007 19:07:51 »
Am I right in thinking that when a magnetic field is generated by a rotating charged ring the field is static?.
What about the case when the ring is made of magnetic materiel does the field rotate in this case?.
 

Offline lightarrow

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another electromagnetism question
« Reply #7 on: 20/09/2007 19:41:08 »
Am I right in thinking that when a magnetic field is generated by a rotating charged ring the field is static?
Ok.
Quote
What about the case when the ring is made of magnetic materiel does the field rotate in this case?.
It depends on how this magnetic material is orientated.
 

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another electromagnetism question
« Reply #7 on: 20/09/2007 19:41:08 »

 

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