Magnetic field of magnet and its defination

AI Thread Summary
The discussion centers on the nature of magnetic fields and how to accurately represent them in diagrams. It highlights that magnetic field lines are often perceived to emerge from the north pole, but in reality, they form a continuous loop. Participants express frustration with drawing field lines, noting that they are not particularly useful beyond indicating a field's general shape. A method is suggested for drawing field lines based on induced poles when a magnet interacts with iron, emphasizing the importance of capturing the induced poles accurately. The conversation concludes with a query about how to approach drawing field lines when both poles of a magnet are exposed to an iron bar.
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When we consider a magnet, usually we perceive the field lines to come out of the north pole. But since the poles of a magnet is actually just a man-defined thing, so actually the magnetic field doesn't emerge from the north but it's a constant loop. So when i draw the magnetic field of a bar magnet in this position, instinctively i will draw it like this: http://postimage.org/image/yzybv7vrl/full/

However if i invert my magnet then i would draw it like this:http://postimage.org/image/sh5ksynwt/full/

So if i take the north pole to be where the magnetic field emerges from, then the two magnetic field diagrams would be different but in actuality the second image should look similar to the first.

Thus, from this I'm confused about how i should draw my magnetic field diagram. Are there any guidelines so that i will draw the correct ones? Thanks for the help!
 
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I hate field lines too - fortunately they're not a very useful thing and you rarely see them being used except as a general indication of a field.

Anyway, the best way to look at is: If you bring a piece of iron near a pole, the pole will induce an opposite pole in the iron nearby. (it doesn't matter if it's a north or south pole)
Then that pole will induce another opposite pole in the iron as far away as it can. If it's a funny shape, it will induce several poles at the farthest points.

Once you've located all the induced poles, you can draw the field lines between them and add in any curves you feel might make it look more smooth.
 
AJ Bentley said:
I hate field lines too - fortunately they're not a very useful thing and you rarely see them being used except as a general indication of a field.

Anyway, the best way to look at is: If you bring a piece of iron near a pole, the pole will induce an opposite pole in the iron nearby. (it doesn't matter if it's a north or south pole)
Then that pole will induce another opposite pole in the iron as far away as it can. If it's a funny shape, it will induce several poles at the farthest points.

Once you've located all the induced poles, you can draw the field lines between them and add in any curves you feel might make it look more smooth.

Haha :smile: we share the same pain. Field lines are so unpredictable. Your method really great! Thanks!
 
AJ Bentley said:
I hate field lines too - fortunately they're not a very useful thing and you rarely see them being used except as a general indication of a field.

Anyway, the best way to look at is: If you bring a piece of iron near a pole, the pole will induce an opposite pole in the iron nearby. (it doesn't matter if it's a north or south pole)
Then that pole will induce another opposite pole in the iron as far away as it can. If it's a funny shape, it will induce several poles at the farthest points.

Once you've located all the induced poles, you can draw the field lines between them and add in any curves you feel might make it look more smooth.

Hello again. I was thinking about this and i thought what if both of the poles are exposed to the iron bar like this. Then how should i approach it? Should i draw both induced poles and from there draw the magnetic field? Something like this: http://postimage.org/image/5n2feusjf/full/

Thanks for the help!
 
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