Wire in E Field: Will it Deflect?

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A current-carrying wire in an electric field may not deflect due to the absence of free charge, but the discussion explores scenarios involving length contraction and potential differences. When a voltage is applied across a suspended wire, it creates an electric field similar to a capacitor, leading to charge separation that could result in forces acting on the wire. The positive and negative charges in the wire would experience opposing forces, potentially causing the wire to rotate. Additionally, if the observer moves relative to the wire, they would perceive a net electric field and a magnetic field, resulting in a Lorentz force that could balance the electric force. Overall, the interaction of electric and magnetic fields plays a crucial role in determining the wire's behavior in these scenarios.
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If I had a current carrying wire in an E field. Would it deflect? The wire it self just has a B field and no free charge. But If I was moving with respect to the wire I would see length contraction and a net E field. So in my frame the wire would deflect. Or is something wrong with my reasoning?
 
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cragar said:
If I had a current carrying wire in an E field. Would it deflect?
I expect it wouldn't. But let's make it more interesting, and use a length of resistance wire so there is significant potential across the wire. (Make it of carbon and delicately suspend it with elastic quartz fibres to avoid arguments.) Would it experience deflecting forces now with a few hundred volts P.D.?
But If I was moving with respect to the wire I would see length contraction and a net E field. So in my frame the wire would deflect. Or is something wrong with my reasoning?
I can't comment.
 
so if we have a suspended wire with a voltage across it, so There is an E field down the wire, so it is basically like a plate capacitor. So if we have a charge separation in the wire
the +q and -q charged will experience forces in the opposite directions and should cancel.
 
cragar said:
so if we have a suspended wire with a voltage across it, so There is an E field down the wire, so it is basically like a plate capacitor. So if we have a charge separation in the wire
the +q and -q charged will experience forces in the opposite directions and should cancel.
I think the more positive end of the wire will be pushed by the E field (i.e., attracted towards the negative plate) and the negative end of the wire will be attracted by the E field (i.e., attracted towards the positive plate), so the wire will tend to rotate about an axis through its centre.
 
So torque on an Electric dipole.
 
Now that I think more about my original post, an looking at this in the moving frame.
If I move with respect to this wire an I get a net E field from the wire, I will also get a B field from the external E field, and this will cause a Lorentz force F= q(vxB) and this will
probably balance the F=qE from the E field.
 
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