Behavior of compasses AFTER the magnetic pole

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SUMMARY

The discussion clarifies the behavior of compasses in relation to the Earth's magnetic poles. A compass points towards the south magnetic pole, which is located near the north geographic pole. When crossing the magnetic south pole, a sensitive compass needle will rotate 180 degrees, indicating the magnetic field's upward direction. Furthermore, in areas between the south magnetic and north geographic poles, the compass will still point towards the magnetic pole, not the geographic pole, regardless of the radial and tangential components of the magnetic field.

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jaumzaum
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So I know that a compass points to the south magnetic pole, that is near the north geographic pole. Let's consider the Earth to be a magnetized bar with all 4 poles aligned (for didactic purposes). The compass will try to "follow" the south magnetic pole, so, if I am in the Equator for example, it will point towards the geographic North. What if I pass the magnetic south pole (I am below the geographic north and above the magnetic south pole)? In my understanding the compass will continue to points towards the south magnetic pole, but in that case it will be pointing towards the opposite way, the geographic south!

Is this statement correct?
 
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No. The way you set up your scenario means the needle will rotate 180 degrees when you step over the south pole.

Provided it's a very sensitive compass: the magnetic field there points skywards !

Wiki pic:

compare lower left needle with lower right

1589497693236.png
 
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BvU said:
No. The way you set up your scenario means the needle will rotate 180 degrees when you step over the south pole.

Provided it's a very sensitive compass: the magnetic field there points skywards !

Wiki pic:

compare lower left needle with lower right

View attachment 262789

Thank you @BvU. Exactly in the magnetic south I am sure it will, but what about a little to the right of it, e.g. in the middle ground of the south-magnetic and north-geographic? I would say the field would have a much higher radial component, but the tangential component there will not be zero, and will make the compass point towards the geographic south, am I right?
 
jaumzaum said:
e.g. in the middle ground of the south-magnetic and north-geographic
I thought that's not in your scenario

jaumzaum said:
magnetized bar with all 4 poles aligned
Did I misinterpret this ? 2 magnetic and 2 geographic is all I could think of.

jaumzaum said:
e.g. in the middle ground of the south-magnetic and north-geographic
...
the compass point towards the geographic south, am I right
Yes. The compass points to the magnetic pole. It does not know about the geographic pole.
 

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