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Re: Magnets repel more weakly than attract

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On 22/06/2016 9:08 AM, omnilobe@gmail.com wrote:
> I did not do the experiment. Do you expect that two similar magnets
> attract with a force F and repel with a force -0.9F at a distance of
> zero between the magnets?
>
> The experiment is simple, but rarely mentioned. The "pull force" is
> measured for a magnet using a spring scale. The attraction force is
> measured and reported as F Newtons for one test. But the force when
> the magnets repel is not reported as "push force".
>
> The lack of standardization of magnet specs might be because of the
> fear of being wrong in some common cases. The manufacturers should
> publish tables of magnet force versus Tesla flux density.
>
> Proposed Theory : two equal permanent magnets attract stronger than
> they repel because of flux bundling. The attracting flux is bundled
> and the repelling flux is diverging. Two North poles facing each
> other must never let flux cross flux, so they diverge. A North facing
> a South magnetic pole does not cross flux lines, it completes flux
> lines, so a tightening of the flux bundle occurs where the two
> magnets touch. Any stray flux gets pulled closer to the attracting
> magnets. But repelling magnets have flux diverging into stray
> locations.
>

It's not as if flux is a real thing, it's just an indication of the 
direction and strength of the field. Clearly, flux lines cannot cross 
because that would mean that the field and strength at the point of 
intersection had more than one value - a physical impossibility.

The field at any point is just the sum the fields of the individual 
magnets at that point.

If you're seeing differences in attraction and repulsion, it's just 
because the field of each magnet affects the other magnet.

Sylvia.

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Magnets repel more weakly than attract omnilobe@gmail.com - 2016-06-21 16:08 -0700
  Magnets repel more weakly than attract john <johnsefton288@gmail.com> - 2016-06-21 16:20 -0700
  Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-21 19:31 -0700
    Re: Magnets repel more weakly than attract omnilobe@gmail.com - 2016-06-21 21:02 -0700
  Re: Magnets repel more weakly than attract Sylvia Else <sylvia@not.at.this.address> - 2016-06-22 15:57 +1000
    Re: Magnets repel more weakly than attract omnilobe@gmail.com - 2016-06-22 08:28 -0700
      Re: Magnets repel more weakly than attract Sylvia Else <sylvia@not.at.this.address> - 2016-06-23 12:07 +1000
        Re: Magnets repel more weakly than attract benj <benj@nobody.net> - 2016-06-23 17:29 -0400
          Re: Magnets repel more weakly than attract Sylvia Else <sylvia@not.at.this.address> - 2016-06-24 10:10 +1000
            Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-24 08:44 -0700
          Re: Magnets repel more weakly than attract Timo <timo@physics.uq.edu.au> - 2016-06-24 15:05 -0700
          Re: Magnets repel more weakly than attract Timo <timo@physics.uq.edu.au> - 2016-06-24 03:36 -0700
          Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-23 16:42 -0700
          Re: Magnets repel more weakly than attract Timo <timo@physics.uq.edu.au> - 2016-06-24 17:56 -0700
        Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-23 15:32 -0700
      Re: Magnets repel more weakly than attract Helmut Wabnig <hwabnig@.- --- -.dotat> - 2016-06-23 07:20 +0200
    Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-22 11:47 -0700
      Re: Magnets repel more weakly than attract benj <benj@nobody.net> - 2016-06-22 16:17 -0400
        Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-22 15:45 -0700
  Re: Magnets repel more weakly than attract "Y.Porat" <y.y.porat@gmail.com> - 2016-06-23 02:32 -0700
  Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-24 08:41 -0700
  Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-23 15:30 -0700
  Re: Magnets repel more weakly than attract "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-06-23 16:41 -0700

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