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jayC
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Four Magnets of Spherical Shape

11/27/2011 2:33 PM

Three magnets (of spherical shape) are placed so as to minimize the energy configuration; that is, they form a triangle; 1) Is the resulting magnetic field entirely in the plane occupied by these magnets?

2) If a 4th magnet is placed on top of the three others, will it be displaced? held in place? or readily removed?

3) Why?
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Ace Boeringa
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#1

Re: Four magnets of spherical shape

11/27/2011 2:56 PM

Jay,

As you claim to have already published ten books it is obvious that you are acutely aware of your superior intellect. What could you possibly hope to learn from a bunch of eggheads like us?
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Usbport
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#2

Re: Four magnets of spherical shape

11/27/2011 3:17 PM

If I take the magnetic BuckyBalls I have and make an equilateral triangle, then try to place a 4th one 'on top', all four immediately rearrange themselves into a square. I can squeeze and hold them into a small pyramid, but as soon as I release the pressure they form a square.

A side note. These have a width:length ratio of 1, and they appear to be more stable in a co-linear arrangement, ••• , than in an equilateral arrangement . It is harder to separate 1 ball from the other 2 when they are co-linear.

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#3
In reply to #2

Re: Four magnets of spherical shape

11/27/2011 5:26 PM

I agree that collinear will hold more strongly in the case of three spherical magnets, but not in the former case of bar magnets where l >> d. [>> = significantly greater.]

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Sapper
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#4

Re: Four magnets of spherical shape

11/27/2011 5:35 PM

All Magnets have two (2) poles North & South...The physical Shape of the magnet is irrelevant, the magnets will there for seek to align the poles or create a closed magnetic circuit.

Therefore with your scenario, they will alight in a collinear for as already noted in another post or complete the circuit, i.e. incorporate the new magnet in a ring.

Any other bond will be weaker and therefore drawn into the linear or circular formation.

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Sapper
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#5
In reply to #4

Re: Four magnets of spherical shape

11/27/2011 6:18 PM

One more thought....with only 4 points (magnets) the only shapes you can make are:

1) Straight line

2) Triangular pyramid

3) a Square

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Sapper

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lyn
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Re: Four Magnets of Spherical Shape

11/27/2011 9:48 PM
  1. Four magnets (of spherical shape) - SciForums.comwww.sciforums.com/showthread.php?p=2864343 - Block all www.sciforums.com results2 posts - 2 authors - Last post: 2 hours agoThree magnets (of spherical shape) are placed so as to minimize the energy configuration; that is, they form a triangle; 1) Is the resulting magnetic field entirely in ...
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  2. Four spherical magnets

If you are doing research for another book, these may help you.Seems others want to know, too.
Now, what's up with you?

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Rixter
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#7

Re: Four Magnets of Spherical Shape

11/28/2011 6:30 AM

Magnetic flux would much rather go through the magnet itself than free space (air), so if your magnets are touching and making a closed loop, most of the flux is contained within that loop. Experiment. Get some iron filings. Put a 3x5 card on top of the magnet and sprinkle the iron filings on top and see.

As you probably know, you can't introduce a fourth magnet without disturbing the other 3. They all share the same magnetic field and they will reconfigure themselves to minimize the magnetic field energy.

Energy in the magnetic field is reduced by first removing air gaps, and second by making the magnetic circuit as short as possible. The forces exerted on the magnets will be in a direction to minimize this energy.
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SolarEagle
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#8

Re: Four Magnets of Spherical Shape

11/28/2011 7:52 PM

Ve haf de purpletual motshun...

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