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Questions about magnetism

  1. Apr 29, 2004 #1
    What is the actual force of magnetism? Why are two permanent magnets attacted to each other? What is the relationship between a permanent magnet and the Earth? What is the relationship between the Earth's magnetic field and the Sun? What is the relationship between a permanent magnet and an electromagnet? Why are certain materials more magnetic than others?
     
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  3. Apr 29, 2004 #2

    Chi Meson

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    That's a lot of questions!
    Electromagnetism is a fundamental force. That means it is what it is and we are still trying to figure out the deeper truth. To learn more detail, study physics for several years (no that was not intended to be condescending, I really mean it!)


    Is this your homework you want us to answer?
     
  4. Apr 30, 2004 #3
    Uh, no, definitely not homework. I was more curious as to whether there was a consistent answer for these questions. I have a few theories of my own and I was wanting to know what the accepted theories were.
     
  5. Apr 30, 2004 #4

    Integral

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    Yes, there are very well formulated theories which can be used to calculate the forces between magnets. Unfortunately they do not lend themselves to brief 25 words or less explanations. As Chi Meson said it takes several years of university level Physics and Math before these theories become very understandable. If you wish to learn more do some web searches on Maxwell's Equations. This set of 4 equations contains the information you are seeking.
     
  6. Apr 30, 2004 #5
    I'm looking for an answer that doesn't involve math. The purpose of math is to explain the rate at which one thing affects another. I'm looking for an explanation of the actual physics that are involved (draw me a picture with words). My understanding is that a permanent magnet's atoms are lined up and that's what gives it it's magnetic properties. But of course lined up atoms themselves aren't producing magnetism, only channeling it from the magnetic core of the Earth. The magnetic core of the Earth would logically collect its energy from the magnetic field of the Sun (the core of the Earth being molten iron and spinning is perfect for this). The magnetic field of the Sun would be the source of all permanent magnets through what I would expect to be a side effect of nuclear fusion itself or in combination with 'something' else. I was pondering how the process in an electromagnet (being capable of producing its own magnetic field independently of the Sun) relates to how magnetism is produced in the Sun. Any thoughts or noticed errors in my understanding would be appreciated.
     
  7. Apr 30, 2004 #6

    Integral

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    Drop this notion, it simply does not work. If the magnetic field of the earth had any effect then the magnets would cease to be magnets when removed from the earth. This is not the case. The magnetic field is due to alignment of atomic level magnetic fields. The Earths field orients this alignment in natural magnets but it does not cause the magnetism. Nor does the sun have any effect on permanent magnets. Drop this line of reasoning.

    True understanding of these phenomena lies in understanding the Math. Arm waving or picture drawing is best for creating misconceptions. If you wish to understand Electro Magnetism you must understand the Math.
     
    Last edited: Apr 30, 2004
  8. Apr 30, 2004 #7
    Where did you get your information about magnets in space. I couldn't find anything about it from a quick search online or in my physics book. Going by my theory, a permanent magnet would still be a permanent magnet until taken out of the Earth's and then the Sun's magnetic field (of course some changes in it's magnetic properties would be expected). The Earth's field orients the allignment in natural magnets by forcing magnetism through them due to the atomic properties of the material (iron, nickel, etc.). It is somewhat similar to if you put a pile of straight sticks in a steady stream of water, they will all line up with the flow of water. The more sticks that line up, the lower the resistance on the water. I am inclined to doubt the accepted belief that the Earth's magnetic field is caused in whole by the spinning of the core. That belief seems to be mostly based on comparing Earth's spin and magnetic field to that of Venus, Mercury, Jupiter, and Saturn (the faster the spin, the stronger the field). Going by that logic, size would also make a difference (Mercury is the slowest and has the weakest magnetic field, Jupiter is the fastest and has the strongest magnetic field). Jupiter, along with having the strongest magnetic field, also has the only magnetic moons in the solar system (Ganymede, Europa, and Io). Io's rotation and orbit around Jupiter match like our moon's rotation and it's orbit around the earth. This halfway supports my theory which considers orbit as having more effect on magnetism than the spinning. Of course Io does still spin (although slow in comparison with it's orbit, it's still spinning a little better than half as fast as earth) so my logic doesn't necessarily dispute the current logic. So I'll draw attention back to the Earth's magnetic field for more explanation of my theory. The Earth's magnetic poles do not match its axis poles. Not only that, but the magnetic poles move around. This doesn't seem to make much sense if the spinning of the Earth is causing the fields. Now if the Earth is just collecting energy from the sun this makes perfect sense. The Earth's magnetic field would always be trying to stay inline with the Sun's magnetic field. Since the Earth rotates on a slight tilt, this would cause a constant moving around of the poles. I still believe that the spinning helps with this process (mainly the alligning of the atoms), but it is not the source of the magnetic energy.

    True understanding of these phenomena lies in understanding and interpreting the math into a scalable model. If the the math can't be made into a model then it is not understood. I agree that 'arm waving' or 'picture drawing' does commonly create misconceptions. I am looking for a picture based on the math (a 3d graph, more or less). I still say the purpose of math is to explain the rate at which one thing affects another. It doesn't explain 'how' one thing affects another. The math wouldn't change by my theory, anyway, because the magnetic effect is the same, but the source is different. Again, any thoughts or noticed errors in my understanding would be appreciated.
     
  9. Apr 30, 2004 #8
    Yep, there are lots of atomic and other processes that rely on magnetism that happen in other galaxys or even in space (away from planets and stars).


    Magnetism is generally caused by the movement of charged particles, while some particles are just fundamentally magnetic (regardless of there movement). This is the "how" of magnetism, and I'm not sure anyone can really think of a "why" for these things at the moment.
     
  10. Apr 30, 2004 #9
    Please inform me of any known magnetic fields that are present without a star or other ball of hydrogen gas (the hydroden is very important).

    If some particles are fundamentally magnetic, then they have to get the energy from a source. If the source is themselves then they are using up inherent energy which going by the laws of thermodynamics would mean that they will eventually run out of that energy (possibly breaking down into less energetic matter). Without an outside source to give them their magnetism, they would cease to exist after a period of time. Given the approximations of the age of the universe, that would mean that there were a lot (a whole lot) more permanent magnets nearer the creation (big bang or whatever). If a permanent magnet is losing energy and that energy is from itself then it would have to be transferring part of its mass to energy. It seems to me that there should be some sort of noticable breakdown over a period of time. If the permanent magnet gets its energy from an outside source then it would show no signs of any breakdown or loss of any kind (unless the magnetic field actually stripped particles off of it).

    The known 'how' is not fact and if a better theory presents itself, then it should be considered. You can't dispute a theory by saying that another theory says it is wrong. I'm looking for an explanation, not a regurgitation of the present theories. I'm not interested in the fact that they are the accepted theories, but 'why' they are the accepted theories.
     
  11. Apr 30, 2004 #10
    http://www.iiap.res.in/answers/galactic.html

    The electron and proton in a hydrogen atom are like 2 bar magnets, normally there north and south poles are anti-alligned (like 2 bar magnets tend to sit). Very rarely the 2 particles make a "spin flip" and by doing this give off a photon of 1429 mHz.

    These photons have been detected from the cold interstellar medium (away from stars and planets)
     
  12. Apr 30, 2004 #11
    The cold interstellar medium just happens to be a body of hydrogen like I predicted. A radio wave is not magnetism. A 21cm wavelength has a frequency below 100mHz (1429 is infrared or microwaves; where did you get that from?). Gonna have to do better than that.
     
  13. Apr 30, 2004 #12
    oops, thats meant to be 14.29 mHz. The magnetism I was refering too is in the proton and electron not the radio wave
     
  14. Apr 30, 2004 #13
    Does this process occur in anything except hydrogen?
     
  15. Apr 30, 2004 #14

    Integral

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    Noah,
    You are beating a dead horse. Natural magnetism is NOT tied to the earth or sun or any other star or planet. Sorry if that disrupts your pet theory. Every atom has a magnetic moment, This is well known and understood property. Have you made any effort to search out information on Maxwell's equations?

    I am well aware of how hard it can be to let go of pet theories but you really need to let go of this crazy idea of yours it simply does not match the universe we live in.
     
  16. Apr 30, 2004 #15
    yes, it occurs in all the elements with nuclear spin in much the same way. I just chose Hydrogen (foolishly =P) because its the simplest element and it was easy to find confirmation of.
     
  17. Apr 30, 2004 #16

    Chi Meson

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    Gosh, that number sounds familiar! :cool:
     
  18. Apr 30, 2004 #17
    I'm beating a live horse. You have yet to dispute any of the deductions that lead to my conclusion. I checked into Maxwell's equations and see no reason that they wouldn't apply the same to my theory as they do to the accepted 'theory'. You shouldn't just tell me I'm wrong and assume I should take that as fact. Find a flaw in my logic and that will actually mean something. That's why I'm posting here. So people can find flaws in my deductions, not just tell me I'm wrong. I meant to write the theory part in the theory forums, but nobody answered what I asked originally. I was originally wanting to get an explanation of the accepted theories of magnetism so I could compare and contrast to my own views, but that was to no avail. So I posted parts of my theory anyway, hoping somebody would actually explain where I went wrong if I am wrong. If you can explain why my theory wouldn't work, then please enlighten me.
     
  19. Apr 30, 2004 #18

    Integral

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    I do not know, nor do I really care, what your theory is. Yes, indeed most planets and stars have magnetic fields. Very weak magnetic fields but they do have them. We are able to create magnets at will and those magnets have properties that are entirely accounted for by Maxwell's equations. Maxwell's equations are not connected to the earths or any other planets or stars magnetic fields. There is no unaccounted for contributions.

    You insistence on arguing your "pet theory" has earned this thread a new home.
     
  20. Apr 30, 2004 #19
    My research seems to indicate that magnetism is the result of a timelike force and electricity is the result of a spacelike force. A timelike force depends on the concept of velocity. And this intrinsic velocity is related to a local acceleration of one dimensional space. Macroscopically speaking, this velocity is related to the speed of light in vacuum. Microscopically, the local acceleration is related to the Planck's constant. Taken together, the local acceleration and a quantum of length, r, formed an invariant.

    [tex] \vec {a} \cdot \vec{r} = c^2 [/tex]
     
  21. Apr 30, 2004 #20
    Noah, reign those horses in!

    Look, a magnet has little to nothing to do with the earth, sun or any galactic resident. It is an internal property of the material.

    If a take 1-inch by 1-inch by 1/4- inch neodymium rare earth magnet, grade 36 that was made on planet earth, and fly it out into interstellar space, it's magnetic properties will be essentially the same at that location.
    Furthermore, if, in interstellar space, I create the same magnet and bring it to planet earth, it's magnetic properties are essentially the same.
     
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