Determine the north pole?

In summary: If not, adjust sympathetically.In summary, the north pole of a bar magnet can be determined by building a scale model of the bigem and observing which direction the needle points.
  • #1
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Homework Statement


Explain how you would determine which was the north pole of a bar magnet, without using any other magnet.


Homework Equations


none


The Attempt at a Solution


If it's small enough you might be able to make it into a compass like object but if its heavy than the magnetic field of the Earth is not strong enough to deflect it. So this might not be 100% correct answer. The answer should encompass all sizes of magnets.
 
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  • #2
Is it allowed to use current carrying wires?
 
  • #3
I think the best way is to use a string/thread and tie it at the middle of the bar magnet. Then just hang it out by holding the string/thread and let it move by itself without applying any force from you hand/fingers as much as possible.
 
  • #4
if that doesn't work, are you allowed to magnetize something much smaller and lighter with the original magnet?
 
  • #5
denverdoc said:
if that doesn't work, are you allowed to magnetize something much smaller and lighter with the original magnet?

As long as that something is not another magnet. But you still couldn't tell which was the north and south pole because if it was steel and you lined the south pole with it, the steel will induce a north side facing the magnet. And vice versa.
 
  • #6
Rubens said:
I think the best way is to use a string/thread and tie it at the middle of the bar magnet. Then just hang it out by holding the string/thread and let it move by itself without applying any force from you hand/fingers as much as possible.

But you still woudn't know which was the N and S pole without another compass , which is a magnet hence disallowed.
 
  • #7
P3X-018 said:
Is it allowed to use current carrying wires?

I think so since the question only said you can't use another magnet. So you are suggesting loop a wire with current around a magnet and notice the direction of the current. This should induce a magnetic field along with the intrinsic magnetic field in the electromagnet (with a magnet core). If the resultant magnetic effect is greater than the place where the current is traveling towards is the N pole and vice versa.
 
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  • #8
pivoxa15 said:
But you still woudn't know which was the N and S pole without another compass , which is a magnet hence disallowed.


Now i know which way north is w/o a compass--are you sure the problem is this constrained? If nothing else you could use the night sky.
 
  • #9
denverdoc said:
Now i know which way north is w/o a compass--are you sure the problem is this constrained? If nothing else you could use the night sky.

I said that another compass was needed because you actually don't know which is N and S on the original magnet (the S will point towards the S and N towards the N but you don't know which is which), which you have made it into some sort of a compass if folllowing Ruben's advice. So you suggest using to the night sky as a guide but you still would need to know which was N and S before hand or find the information in a book. But the original people who found out had to use a proper compass hence another magnet. In this way I think the way suggeted by P3X-018 and elaborated by myself is a better answer to the question. The question clearly stated that another magnet cannot be used.
 
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  • #10
I guess I'm properly confused, owing much to my igorance, no doubt. My thinking was as follows, A big bar magnet suspended on however frictionless a bearing will be under the most minute torque. I have no idea,but guessing it could hang for days or weeks, months centuries even, So assuming its a compass its in its own right, we need to either make a Focault like pendulum and wit saa long time or diminish the inertia-thatis sympathetically magnetize a needle, paying attention to orientation, and stick the now low mass N/S indicator into a cork, whatever,

Basically build a scale mod of the bigem, If it points toward Polaris, bingo
 

1. What is the difference between the geographic north pole and the magnetic north pole?

The geographic north pole is the northernmost point on Earth's surface, where all lines of longitude meet. The magnetic north pole, on the other hand, is the point where the Earth's magnetic field is directed vertically downward. This means that a compass needle will point towards the magnetic north pole instead of the geographic north pole.

2. How does one determine the north pole?

The north pole can be determined using a combination of geographic coordinates and magnetic declination. Geographic coordinates can be obtained using GPS or by using a map and compass to determine latitude and longitude. Magnetic declination, or the angle between true north and magnetic north, can be found using a compass or through online resources.

3. Why is it important to accurately determine the north pole?

Determining the north pole accurately is important for navigation and surveying purposes. It allows us to determine our location on Earth and navigate to specific destinations. It is also important for scientific research and exploration in the polar regions.

4. Can the north pole shift or change over time?

Yes, the magnetic north pole can shift and change over time due to changes in the Earth's magnetic field. It has been observed to be moving towards Siberia at a rate of about 55 kilometers per year. However, the geographic north pole remains fixed at the Earth's rotational axis.

5. How does the north pole affect climate and weather patterns?

The north pole plays a significant role in climate and weather patterns, particularly in the Arctic region. The Earth's rotation and the tilt of its axis towards the north pole result in the polar jet stream, which influences weather patterns in the Northern Hemisphere. The north pole also plays a crucial role in regulating global climate through its impact on ocean currents and sea ice formation.

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