The force between current carrying conductors

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Discussion Overview

The discussion revolves around the forces between two long, current-carrying conductors in free space, specifically addressing the implications of these forces on Newton's Third Law. The scope includes conceptual clarifications and technical reasoning related to the behavior of the forces under different conditions, such as wire length.

Discussion Character

  • Conceptual clarification, Debate/contested

Main Points Raised

  • One participant asserts that the force per unit length between two long, current-carrying conductors is equal, but questions whether this implies that the total forces on the conductors are also equal, raising concerns about Newton's Third Law.
  • Another participant questions the reasoning behind the assertion that the two wires would not experience the same total force.
  • A clarification is made regarding the term "long," indicating that it refers to infinitely long conductors.
  • A further participant introduces the idea of considering the scenario where the wires are not infinitely long, suggesting that this may affect the analysis of forces.

Areas of Agreement / Disagreement

Participants express differing views on whether the total forces experienced by the conductors can be considered equal, indicating that the discussion remains unresolved with multiple competing perspectives.

Contextual Notes

The discussion may be limited by assumptions regarding the ideal conditions of the conductors, such as their lengths and the nature of the currents, which have not been fully explored.

PFuser1232
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For two long, current-carrying, straight conductors in free space, the force of attraction (or repulsion) per unit length between the wires is the same. That is, the force per unit length experienced by the first wire, is the same as the force per unit length experienced by the second wire. But the force experienced by the first wire as a whole may not necessarily equal the force experienced by the second wire as a whole. Doesn't this violate Newton's Third Law? Where am I getting this wrong exactly?
P.S. I'm an A level Physics and Mathematics student, so that's how far my knowledge in Physics and Mathematics goes.
 
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Why would the two wires not experience the same total force?
 
"long" in this sense means infinitely long.
 
Suppose the wires are not infinitely long
 

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