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Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: ciniva on 14/09/2017 11:08:08

Title: What arrangement of magnets produces the greatest magnetic field strength?
Post by: ciniva on 14/09/2017 11:08:08
My apology if I made a mistake to the forum group. Please moderator to move the thread to the appropriate group.

Since I do not have an instrument for measuring the strength of the magnetic field, I thought to ask the here.
I seek the help of experienced experts who understand in magnets, magnetic field lines and the power of the magnetic field.
Which of these three variants in the picture has the strongest magnetic field in the ellipse zone in the north pole of magnets (whether it is a single magnet or multiple connected to one and which zone).
Zone 1a, 2a and 3a are located opposite the magnets,
Zone 1b, 2b and 3b are under 45° degrees.
Does anyone have any experience or perhaps an gaussmeter that can measure the strength of a magnetic field on their own?
I'm interested in the greatest distance at which will begin to attract other magnet (or a piece of metal)
Where is the power of attraction of the magnet stronger. Opposite or under 45° degrees? and which variant?

* aaasss.png (15.1 kB . 874x661 - viewed 16241 times)
Title: Re: What arrangement of magnets produces the greatest magnetic field strength?
Post by: Kryptid on 14/09/2017 22:59:41
As you add more and more magnets of decreasing size in a north-to-south configuration, you eventually reach a point where the net magnetization approaches zero (i.e. the distribution of north and south poles becomes increasingly homogeneous inside of this compound magnet). For this reason, I say the single magnet approach has the strongest field.
Title: Re: What arrangement of magnets produces the greatest magnetic field strength?
Post by: ciniva on 15/09/2017 21:05:42
Helo Kryptid
Thanks for your feedback and suggestions. I'll take this answer seriously.
Whether it is just your opinion or the result of your experience. I do not have a measuring instrument.

Still, I will wait for other members of the forum to say their opinion.
Title: Re: What arrangement of magnets produces the greatest magnetic field strength?
Post by: Colin2B on 16/09/2017 10:42:42
Helo Kryptid
Thanks for your feedback and suggestions. I'll take this answer seriously.
Whether it is just your opinion or the result of your experience. I do not have a measuring instrument.

Still, I will wait for other members of the forum to say their opinion.
You should definitely take Kryptid's feedback seriously. Based on the quality of previous answers  the reply is based on both knowledge and experience rather than opinion.

In addition I would say:
Practical magnets are rarely perfectly smooth or have coatings, this reduces the quality of contact between the magnets and reduces the overall strength of a stack.

The stack should not be higher than the diameter of the magnets, beyond this the strengths do not add together, but start to decrease towards a limiting value. As an example with measurements of 10mm dia x 1mm thick magnets
Number of magnets.             Force
1.                                                 0.5
2.                                                 1.0
3.                                                  1.5
4.                                                  1.9
5.                                                  2.1

It's also worth noting that in a stack of magnets the attraction between the 2 end magnets is often less than that between the end of the stack and the metal object being attracted.


Hope those points help.
Title: Re: What arrangement of magnets produces the greatest magnetic field strength?
Post by: ciniva on 17/09/2017 07:29:39
Hello Colin2B
Thank you to confirm the Kryptid's answer. I'm new to the forum, This is my first thread and I did not think underestimate anyone's answers.
I just want to get the answer of a person who has a practical experience.
My mistake was that I did not research Kriptid's profile and looked at other posts.

This your additional explanation to me is enough.

I have an additional question in the first post.
So in this case in the image the strongest force of the magnet is "variant 3"
Considering the arrangement of magnetic field lines in the magnetic field on N pole, where is the magnetic force stronger. In the opposite (3a) area or at a 45-degree angle (3b) area?
I hope my question is understandable.
Best regards
Title: Re: What arrangement of magnets produces the greatest magnetic field strength?
Post by: ciniva on 17/09/2017 20:15:48
Quote
The stack should not be higher than the diameter of the magnets, beyond this the strengths do not add together, but start to decrease towards a limiting value.
Does this mean that two magnets that are of the same characteristics but of different dimensions, had the same power of attraction on the N pole?
In the image below both magnets have a diameter of approximately 30mm (as well as the thickness of the magnet).
Or maybe I still do not understand something. Which magnet has a stronger force A or B

 [ Invalid Attachment ]

Best regards
Title: Re: What arrangement of magnets produces the greatest magnetic field strength?
Post by: ciniva on 19/09/2017 14:31:12
Can someone with experience give me an answer to post #4 and #5? Thanks in advance.
Title: Re: What arrangement of magnets produces the greatest magnetic field strength?
Post by: Kryptid on 19/09/2017 15:47:33
Can someone with experience give me an answer to post #4 and #5? Thanks in advance.

Both magnets have the same height, but magnet A has more total volume (and presumably material) than magnet B, 13,320 cubic millimeters vs. 10,123 cubic millimeters. All else being equal, magnet A should be the stronger of the two.

As to your other question, area 3b appears to be closer to the magnet north pole than area 3a, so the field should be stronger there.
Title: Re: What arrangement of magnets produces the greatest magnetic field strength?
Post by: ciniva on 20/09/2017 19:28:03
Hi Kryptid
Thank you for your reply.
Best regards

Thread can be closed.