Is the Right Hand Rule for Magnetism Really Necessary?

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Discussion Overview

The discussion revolves around the necessity and application of the Right Hand Rule in magnetism, particularly in relation to the direction of forces on charged particles and current-carrying conductors. Participants explore whether alternative methods, such as using the left hand for negative charges, could simplify understanding for students.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions the necessity of the Right Hand Rule, suggesting that using the left hand for negative charges could be more logical and easier for students.
  • Another participant references Fleming's left hand rule, implying that introducing multiple rules could lead to confusion.
  • A different viewpoint argues that regardless of the charge of the particle, the Right Hand Rule still applies, as the vector direction for negative particles is simply opposite.
  • Concerns are raised about whether it is more confusing for students to remember to switch the direction of the force rather than using a left hand rule for negative charges.
  • One participant asserts that the Right Hand Rule is a convention, and consistency with this convention is what matters, regardless of the charge of the particles involved.

Areas of Agreement / Disagreement

Participants express differing opinions on the effectiveness and necessity of the Right Hand Rule, with no consensus reached on whether an alternative method would be beneficial or less confusing.

Contextual Notes

Participants highlight the potential for confusion in teaching methods and the implications of using different conventions, but do not resolve the underlying assumptions about the effectiveness of the Right Hand Rule versus alternative approaches.

pray_for_mojo
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All of the books and experience I can find offer only a Right Hand Rule for magnetism (current in a wire, particles). Since this is good for only positive particles, students must remember to switch the direction of the force when using the rule. Why not just use the left hand for negative and the right for positive? Am I missing something? It seems the easier and more logical way to go.
 
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Well flemming stole the left hand rule for showing the force on a current carrying conductor in a magnetic field. I presume it would just be confusing if there was an alternative for each one.
 
I would think that with a negative particle, the vector is pointing in the opposite direction, so you really still need to apply the right hand rule.
 
If the field and the velocity are the same the only difference is in the direction that your thumb is pointing (force). For students new to physics, is it more confusing to suggest they remember to switch the direction of the force in their minds as opposed to using their left hand? ...Fleming aside...
 
The right hand rule is just a convention. As TheDude said, you always apply the right hand rule, even for negative particles. We could just as easily have decided to use a left-hand rule, and everything would work just the same -- theories would still make the same predictions. All that matters is that you are consistent with the convention.

The presence of such a choice is actually a rather deep characteristc of our physical universe. It turns out that the concepts of a vector and a dual vector are different in spaces of all dimension except three; the cross-product and its freedom for a convention can only exist in three dimensions.

- Warren
 

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