Direction of H Field Lines: North to South or South to North?

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Discussion Overview

The discussion revolves around the direction of H field lines in relation to magnetic poles, exploring whether they go from north to south or vice versa. It includes references to definitions and relationships between H and B fields, as well as interpretations of statements from external sources like Wikipedia.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant asks whether H field lines go from north to south or south to north.
  • Another participant asserts that H field lines go from the north pole of a magnet to the south pole.
  • A participant expresses confusion regarding a Wikipedia statement that suggests H-field lines start near the south pole and end near the north pole, questioning its accuracy.
  • Another participant suggests that the Wikipedia statement may not refer to the direction of the field.
  • A participant references the equation B = H + M and discusses the implications for H field lines, noting that B lines cannot begin or end and that M is uniform inside the magnet and zero outside.
  • A later reply indicates that while H and B field lines are the same outside the magnet, they would be further apart inside due to the opposite direction of M.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the interpretation of the Wikipedia statement, and there are competing views regarding the direction and behavior of H field lines in different regions relative to the magnet.

Contextual Notes

There are unresolved aspects regarding the definitions of H and B fields, as well as the implications of the relationship between these fields and magnetization (M). The discussion reflects varying interpretations of external sources and the conditions under which the statements apply.

lavster
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does the H field lines go from north to south, or south to north?

thanks
 
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The H field lines go from the N of a magnet to the S.
 
thanks! that's what i would have guessed. :) so what does this statement on wikipedia mean? is it wrong?

"Outside a magnet H-field lines are identical to B-field lines, but inside they point in opposite directions. Whether inside or out of a magnet, H-field lines start near the S pole and end near the N."

cheers
 
They probably don't mean the direction of the field.
 
B = H + M, right? Lines of B can never begin or end, and M is uniform inside the magnet and 0 outside. What does that tell us about H?
 
ah right kl :) so the field lines are the same out side as the B field but inside the field lines would be further apart as M is in the opposite direction.
cheers
 

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