Why dont magnets around earth fly towards the earths magnetic poles?

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Discussion Overview

The discussion revolves around the reasons why magnets do not fly towards Earth's magnetic poles, exploring the strength of Earth's magnetic field, the forces involved, and the nature of magnetism itself. Participants engage in both theoretical and conceptual inquiries regarding magnetic forces and their calculations.

Discussion Character

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

Main Points Raised

  • One participant questions the force required for a magnet to be pulled towards Earth's magnetic poles and how to calculate the necessary strength of a magnetic field.
  • Another participant notes that the Earth's magnetic field at the surface is weak, in the microtesla range, compared to stronger lab magnets, which are around 10 teslas.
  • A participant inquires about the specific force of Earth's magnetic field acting on a small compass and what strength is needed to pull on a magnet.
  • It is mentioned that the Earth's magnetic field pulls on all magnets, and the analogy is made comparing this to a wind not being strong enough to move heavier objects like cars, while it can affect lighter objects like feathers.
  • One participant expresses confusion about the nature of magnetism, questioning how to predict magnetic forces and the role of free electrons in magnetic attraction.
  • Another participant discusses the behavior of free electrons in a paper clip when exposed to magnetic poles, suggesting that they contribute to the attraction.
  • There is a mention of the limited number of magnetic metals and a reflection on the general understanding of magnetism from school days.
  • A question is posed about whether a magnet will consistently land in the same orientation if dropped multiple times.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and confusion regarding magnetism, with no consensus on the specific mechanics of magnetic attraction or the calculations involved. Multiple competing views and questions remain unresolved.

Contextual Notes

Participants highlight limitations in their understanding of magnetism, including the dependence on definitions and the complexity of magnetic forces, without resolving these issues.

mapa
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Why don't magnets fly to Earth's magnetic poles? I understand that Earth's magnetic pull must be strong enough to pull a magnet to the pole, but what is the force required for a magnet to get pulled the over their? How does one calculate whether a magnetic field is strong enough in order for two magnets to pull into each other?
 
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At the surface of the Earth the magnetic field is very weak, in the region of microteslas. A strong lab magnet is about 10 teslas for comparison. We can walk past most labs without having metal object snatched from our hands afterall! The magnetic field at the Earth's core is substantial, but remember that we are about 6400km away from it!
 
On a compass there is a force pulling on its magnetic poles. What is the force of the Earth magnetic force acting on a small compass? How strong does the Earth's poles need to be in order to pull on a magnet?
 
Same force, order of microteslas, compass needles are very light so are easily moved.

The Earth and the magnet pull on each other. The Earth's magnetic field pulls on all magnets.

I suppose its a bit like asking why a westerly wind doesn't blow all the cars into the ocean, since it does for feathers.

Are you simply asking what is the force between two magnets of of known strength?
 
Well I was looking for the strength of the Earth's magnetic field acting on an object.
 
The strength of the Earth's magnetic field isn't something that depends on the thing you're testing it with. The forces and accelerations due to the Earth's magnetic field change though [pedantic language point].

I really don't understand magnetism, despite knowing enough mathematics to model quite a lot of phenomena caused by it.

Where does the magnetic force come from? Or how do we predict it?

F=qvXB I know, but what are the q's and v's in a paper clip that gets stuck to a magnet?
(Free electrons?)

For the electrostatic charge, we can say "Right, this thing is + and that thing is -, so they should both experience a coulomb force towards each other". Norths attract souths is the analogue, but both also attract paper clips.
What's that about?

Where does "norths attract souths" appear in the equations anyway? What is a north pole?
(I seem to remember, once had a problem on a sheet that asked to prove that a magnetic dipole is like a tiny circuit loop...but I never did it and don't remember the answer x.x)
 
I could be wrong here but about the paper clip thing.

There are free electrons in the paper clip, when put at a positive pole, the electrons are attracted towards it holding onto it.

When put at a negative pole the electrons are pushed to the far side of the paperclip, giving the side closest to the pole a 'positive' value, therefore attracting again.
 
I thought all metals had free electrons though, not just magnetic ones (of which there are fairly few I think? Fe, Ni, Co? God, school feels so long ago)
 
If you drop a magnet a couple times will it land one way or the other over and over?
 

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