What is wrong with Ampere's force law?

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Discussion Overview

The discussion revolves around the validity and applicability of Ampere's Force Law, particularly in relation to finite versus infinite wire lengths. Participants explore the implications of using this law in practical scenarios and compare it with the Lorentz force equation.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • Some participants question whether Ampere's Force Law represents the force felt by each wire or the total force between two wires, suggesting it may be inadequate due to its dependence on infinite wire assumptions.
  • Others assert that the law applies to each 1-meter section of infinitely long wires, indicating that it produces consistent results regardless of wire length.
  • Concerns are raised about the practical applicability of Ampere's Force Law, with some arguing that it is useless for real-world scenarios involving finite wires.
  • Participants discuss the relationship between Ampere's Force Law and the Lorentz force equation, with some claiming that both equations yield the same results when considering force per unit length.
  • There is contention over whether the equations can be reconciled, with some insisting that the Lorentz force includes wire length as a relevant parameter, while others argue that both equations should produce the same force per unit length for infinite wires.
  • Disagreement exists regarding the interpretation of the equations, with some participants demanding clarification on how the concept of "per unit length" is derived and its relevance to finite wires.
  • Some participants reference the Biot-Savart law in the context of calculating forces, emphasizing the limitations of Ampere's Force Law when applied to finite wires.

Areas of Agreement / Disagreement

Participants do not reach consensus on the applicability of Ampere's Force Law to finite wires versus infinite wires. Multiple competing views remain regarding the interpretation and utility of the equations involved.

Contextual Notes

Limitations include the assumption of infinite wire lengths in Ampere's Force Law, which may not hold in practical applications. The discussion also highlights unresolved mathematical steps and the dependence on definitions of force per unit length.

  • #31
Dunnis said:
One ampere IS one coulomb per meter per second

No, it is not. It is 1 C/s. As the equations you posted said.

Anyway, your question has been answered, over and over again. If you choose not to accept the answer, there's not much more to be done. We might as well close this thread.
 

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