Help are any of these even correct?

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Homework Help Overview

The discussion revolves around the orientation of a bar magnet in relation to Earth's magnetic and geographic poles. Participants are examining the reasons why the north pole of a bar magnet points north, considering various statements about the nature of Earth's magnetic field and the definitions of magnetic poles.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the definitions and relationships between geographic and magnetic poles, questioning the accuracy of multiple statements regarding their alignment and characteristics. Some express uncertainty about the explanations provided and suggest alternative interpretations of magnetic behavior.

Discussion Status

The discussion is ongoing, with participants providing differing viewpoints on the nature of magnetic poles and their implications. Some guidance has been offered regarding the terminology and concepts, but there is no explicit consensus on the correct answer to the original question.

Contextual Notes

Participants note the complexity of the topic, including the movement of the magnetic north pole and the distinction between geographic and magnetic definitions. There is also mention of the potential for misinformation in media representations of these concepts.

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I've done some background research but can't find a definite answer to this question. At first i suspected the answer to be A but everyone seems to have their own thoughts about it:

The reason the north pole of a bar magnet (which is free to rotate) points north is because:

a. the south geographic pole of the Earth is the Earth's magnetic north pole

b. the south geographic pole of the Earth is the Earth's magnetic south pole

c. there is a net accumulation of negative charge at the Earth's south geographic pole

d. there is a net accumulation of positive magnetic charge at the Earth's north geographic pole

e. the north geographic pole of the Earth is the Earth's magnetic north pole

i'm pretty sure c and d can be eliminated but that still doesn't make the question much easier to answer
 
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They are all wrong.

The geographic and magnetic poles do not coincide.

A magnet aligns itself with the magnetic field lines.

The magnetic field lines stretches from the north pole towards the south pole of a magnet. This means that the noth pole of a magnet will point towards the south pole of another magnet (unlike poles attrack each other). The N point of a compass is therefore actually the south pole of a magnet.
 
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I'm not quite sure that explanation is quite correct.

This explanation may work better for you. When the phenomenon was first discovered, it was noticed that one end of a bar magnet would orient itself toward Earth's North Pole. This end of the bar magnet was called the north-seeking pole, or shortened, N. So, your bar magnet has two poles: N and S. The S is really the "south seeking pole."

Now, if you think about magnets merely as having "north and south poles", then for the north pole of a magnet to be attracted to Earth's north pole, then Earth's north pole is actually a magnetic south pole. This really isn't a problem though, because it means "south seeking pole" - which of course, opposite poles of a magnet are attracted to each other, thus regardless of what we call Santa Claus country, it's going to be attracted to penguin-land.

A compass needle points in the direction of the magnetic field. Lines of flux are drawn from North to South. So, it will orient itself pointing to the "S" on a bar magnet. In order for it to do this, the tip of the compass needle (on the side it points to) must be a "N-pole". Thus, a compass points toward "S", and Earth's North pole is a magnetic S-pole.
 
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Oh, and for what it's worth, choices b and e are essentially the same. You are correct that it's answer A, although andrevdh is correct in pointing out that the geographic north pole and magnetic north pole are not in the same place.

I should emphasize though, it's called "The Magnetic North Pole" - it IS the North Pole. And, of course, as a north pole, it's going to be south-seeking. Bar magnets are labeled by which pole they're seeking, so if you label the Earth as a bar magnet (and in reality, the source of the magnetic field is NOT bar shaped; that's another discussion though) then you need to label that thing up in the Arctic Ocean a "south-seeking pole" or S. But, again, it IS the Magnetic North Pole.

And, as andrevdh noted, it's not located at the geographic north pole. Plus, it moves around a bit, varying daily, and changing location by about 10 to 50 kilometers each year. The changing location of the magnetic north pole hasn't been missed by the media. They love to sensationalize on such things; there were several such stories a few months ago.

Here is a site that seems to have some quality info, if you need more:
http://gsc.nrcan.gc.ca/geomag/nmp/northpole_e.php
 
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