Do magnetic poles of an object have to be perpendicular to the object's surface?

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Discussion Overview

The discussion centers around the orientation of magnetic poles in relation to the surface of an object, specifically whether they must be perpendicular to that surface. Participants explore theoretical implications, practical observations, and conceptual clarifications regarding magnetic fields and dipoles.

Discussion Character

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

Main Points Raised

  • One participant questions if the poles of a bar magnet can point in orientations other than 90 degrees and 180 degrees.
  • Another participant suggests that while poles can point in various directions, the magnetic field may be weaker and take on an unusual shape in those orientations.
  • It is asserted by a participant that poles do not have a direction but rather a location, challenging the conventional understanding of magnetic poles.
  • One participant states that magnetic flux lines are always normal to the surface at a pole, implying a specific relationship between poles and surface orientation.
  • Another participant elaborates that the concept of magnetic poles is a loose visualization tool, indicating that magnetization can occur throughout an object and that poles can be located anywhere depending on how the object is magnetized.
  • A further contribution discusses the ambiguity of the term "magnetic dipole," noting that magnetic field lines are not always normal to the surface and referencing the Biot-Savart law to explain the relationship between current direction and magnetic field orientation.

Areas of Agreement / Disagreement

Participants express differing views on the nature of magnetic poles and their orientation relative to surfaces. There is no consensus on whether poles must be perpendicular to the surface, and multiple competing perspectives remain unresolved.

Contextual Notes

Participants highlight limitations in the definitions and conceptualizations of magnetic poles and dipoles, as well as the dependence on specific conditions such as the shape of the object and the uniformity of magnetization.

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Topic. If I have an iron shaped like a bar magnet placed flat on the floor, can the poles of the magnet be pointing anywhere else other than 90 degrees and 180 degrees?
 
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They can. But I would expect that the field you can get with unusual orientations is a bit weaker, as the magnetic field gets an odd shape.
 
The poles don't point. They have no direction. Just a location.
 
Magnetic flux lines are always normal to the surface at a pole.
 
The poles can be located anywhere on an object depending on how you magnetize it. By the way, the concept of macroscopic "poles" is a loose conceptual entity that helps visualize thing. There is no exact pole location - a single point in space - where a little physical thing called a pole sits. Rather, a material can have a magnetization throughout its extent. If the magnetization is fairly uniform and the object's shape is fairly simple, then it looks like all the field lines are created by two poles on opposite sides of the object.

For example, four loops of current-carrying wire produce the magnetic field shown below. Where exactly would you say is the location of the poles?

220px-VFPt_quadrupole_coils_1.svg.png
 
A "magnetic dipole" is, as described above, a vague and ambiguous term. Indeed, magnetic dipoles do not even exist in nature (div(B) = 0, always). In a general sense, though, all magnetic field lines are not always normal to the current-carrying surface.
This follows directly from the Biot-Savart law, in the general case of a surface current:

B(r) = \frac{\mu}{4\pi} \int \frac{K(\acute{r}) χ \hat{r}}{r^2}d\hat{\tau}

where K(\acute{r}) is the surface current density,
and \hat{r} is the vector extending from the source to the point r

We note that the direction of the magnetic field will be given by the cross product between a vector pointing in the direction of the current and a vector pointing towards the point. Ergo, the magnetic field lines must always be perpendicular to the direction of current, but may not be perpendicular to the surface itself.
In your particular case, the field lines will always be perpendicular to the outer edges ("dipoles") of the bar.
Hope this helped. :3
 
Thanks to everyone who's helped. My question has been adequately answered :)
 

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