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Re: Magnets repel more weakly than attract

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On 24/06/2016 7:29 AM, benj wrote:
> On 6/22/2016 10:07 PM, Sylvia Else wrote:
>> On 23/06/2016 1:28 AM, omnilobe@gmail.com wrote:
>>> On Tuesday, June 21, 2016 at 7:57:51 PM UTC-10, Sylvia Else wrote:
>>> "It's not as if flux is a real thing, it's just an indication of the
>>> direction and strength of the field."
>>>
>>> Flux is real. It is different from gravity and similar in ways. Flux
>>> penetrates rocks and lithium metal with real effectiveness.
>>>
>>> "Clearly, flux lines cannot cross".
>>>
>>> A law is born. When matter cuts flux, a generator is possible. Matter
>>> has area called charge that cuts flux.
>>>
>>> "If you're seeing differences in attraction and repulsion, it's just
>>> because the field of each magnet affects the other magnet. Sylvia."
>>>
>>> I am imagining a weaker repulsion because no data is available to
>>> confirm the difference between magnets that repel or attract. Where
>>> are the numbers? Where is the formula? I bought a book on linear
>>> motors and actuators, but they are also trying to figure this out. It
>>> is complicated and it depends in shape, domains, and surroundings.
>>> Their formulas are not good enough to answer the questions of a 12
>>> year old hobbyist. Magnets need more measurements and reports to
>>> satisfy people who expect better of science than the improvised rules
>>> of thumb.
>>>
>>> Billions of dollars are wasted looking for black holes, dark matter,
>>> and magnetars, but on Earth, ordinary magnets are ignored. Even a
>>> basic repulsion fact is just because of a field that is never
>>> described mathematically in sufficient detail.
>>>
>>
>> Consider how a magnet interacts with a non-magnetised piece of iron. The
>> field of the magnet causes domains in the iron to orientate themselves
>> according to the field. The result is that the magnet attracts the iron,
>> which is temporarily magnetised.
>>
>> Now consider two magnets. When orientated so that they attract, the
>> field of each causes further alignment of the domains in the other, and
>> that alignment reinforces the field, increasing the attraction.
>>
>> Now orientate the magnets so that they repel. The field of each reduces
>> the field that's orientating the domains in the other. Some of those
>> domains lose orientation, reducing the total field. Net result - a lower
>> repulsive force than there was previously an attractive force.
>>
>> So there's nothing to see here. Move along.
>>
>> Sylvia.
>
> Great theory "Sylvia" but you don't have much to back it up. You know
> they are called permanent magnets because the domains DO NOT "lose
> orientation" unlike iron. I'm sure one might propose a slight spring
> like deflection of domains which snap back once field is gone, but I
> doubt this effect is significant. In fact, I doubt there are very few
> credible measurements of ANY of this including the alleged difference
> between attraction and repulsion.
>
>

The fact that they're permanent magnets only means that some of the 
domains have persistent orientations. It doesn't mean that every domain 
in the magnet does.

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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