What are the Forces on parallel ac conductors

AI Thread Summary
Two parallel conductors, A and B, carrying AC currents with a wavelength of λ, are separated by λ/4 and have a phase difference of λ/4. Conductor A experiences a force toward conductor B due to the in-phase field from B, while conductor B experiences a force away from A due to the 180° out-of-phase field from A. This creates a scenario where both conductors seem to be pulled towards each other, suggesting a net force. However, the discussion raises the question of why this movement does not occur. The varying magnetic fields and their effects on the conductors are central to understanding this phenomenon.
Tracer
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The Scenario:
Two long parallel conductors A and B are carrying an ac current with a wave length of λ. The conductors are separated in distance at all points by λ/4 and the ac current phase of conductor A leads the ac current phase of conductor B by λ/4 at all points mutually at right angles between the two conductors.
The Problem:
Conductor A will always be in a field radiated from Conductor B that is exactly in phase with the actual phase of conductor A's current. Consequently conductor A will experience a force directed toward conductor B.
Conductor B will always be in a field radiated from conductor A that is exactly 180° out of phase with with the actual phase of conductor B's current. Consequently conductor B will experience a force directed away from conductor A.
Since forces on both conductors are in the same direction it seems that a net force would exist that would tend to move both conductors in a direction from conductor A towards conductor B.
The question: Why will this not happen?
 
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Hi Tracer! :smile:

What is the effect of the varying magnetic field?
 
tiny-tim said:
Hi Tracer! :smile:

What is the effect of the varying magnetic field?

Aside from inducing currents in other conductors?

This is not a homework problem tiny-tim. It is a scenario that I have never seen addressed anywhere.
a more graphic of the problem is presented in the EMRPHASES1.doc atachment.

Regards, Tracer.
 

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