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Thread: Magnetic properties

  1. #1 Magnetic properties 
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    I am going to start off with a question before I say what I observed.

    Does aluminum, or any type of aluminum with potential slight impurities react with a magnetic field in any way? If so, how can it react?


    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

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    The spinning disc in your electric meter is aluminum. It reacts to magnetic fields by means of induced eddy currents. Read about it here.

    http://en.wikipedia.org/wiki/Electricity_meter


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    Yes, I thought of eddy currents, but it does not seem like it is enough to do what it is doing....or even can behave that way. Any more ideas?
    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

    "Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence"

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  5. #4 Re: Magnetic properties 
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    Quote Originally Posted by Cold Fusion
    I am going to start off with a question before I say what I observed.

    Does aluminum, or any type of aluminum with potential slight impurities react with a magnetic field in any way? If so, how can it react?


    Heck you can make ambient radiation push it up to an electro magnet. What we usually call attract.


    This shows a niobium magnet effecting aluminum. However I would have to say that the movement could be setting up conduction in the aluminum. The aluminum in the case of the "U" channel is type 6063 aluminum.

    http://www.Rockwelder.com/WMV/Magnetism/Magnetism.html

    This shows an aluminum washer being lifted to a magnet. I do not know the alloy of the washer. However it is a common manufactured, aluminum washer.

    http://www.Rockwelder.com/WMV/AlumEl...tromagent.html


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  6. #5 Re: Magnetic properties 
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    Quote Originally Posted by Cold Fusion
    I am going to start off with a question before I say what I observed.

    Does aluminum, or any type of aluminum with potential slight impurities react with a magnetic field in any way? If so, how can it react?
    Aluminium (pure) is affected by a magnetic field only when it is conducting electricity. It may also react if it is alloyed with iron, with iron as a major component of the alloy.
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  7. #6 Re: Magnetic properties 
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    Quote Originally Posted by PritishKamat
    Quote Originally Posted by Cold Fusion
    I am going to start off with a question before I say what I observed.

    Does aluminum, or any type of aluminum with potential slight impurities react with a magnetic field in any way? If so, how can it react?
    Aluminium (pure) is affected by a magnetic field only when it is conducting electricity. It may also react if it is alloyed with iron, with iron as a major component of the alloy.

    Iron is only magnetic if it is conducting electricity.


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    And if it is alloyed with iron it can only attract, right?

    Well, I guess I'll get to it. Essentially, when I dropped the aluminum on my neodymium magnet, the aluminum was "buffered" while falling, as in it acted as if it fell into a very dense liquid. When I pulled it out of the field it resisted, again as if in a dense liquid. The only explanation I have for this is that eddy currents form due to the movement of the aluminum inducting current by passing through the magnetic field. This would create a form of neutral repulsion and attraction.

    What do you guys think of this? It funny that through none of the advanced physics courses I took in high school they mentioned this effect.
    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

    "Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence"

    -Einstein

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    Quote Originally Posted by Cold Fusion
    And if it is alloyed with iron it can only attract, right?

    Well, I guess I'll get to it. Essentially, when I dropped the aluminum on my neodymium magnet, the aluminum was "buffered" while falling, as in it acted as if it fell into a very dense liquid. When I pulled it out of the field it resisted, again as if in a dense liquid. The only explanation I have for this is that eddy currents form due to the movement of the aluminum inducting current by passing through the magnetic field. This would create a form of neutral repulsion and attraction.

    What do you guys think of this? It funny that through none of the advanced physics courses I took in high school they mentioned this effect.

    You can repel steel with an electromagnet. You can attract steel with an electromagnet. Electric common repulsion induction motors repel the rotor.

    You can attract or repel aluminum with an electro magnet.

    Actually originally according to Faraday, there were two classifications of materials, paramagnetic and diamagnetic. Paramagnetic materials were attracted by strong magnetic fields. While diamagnetic materials were repelled by strong magnetic fields.

    Liquid oxygen like iron, is also a paramagnetic. However you will have a hard time proving it.

    Aluminum, copper, glass wood and paper, are all diamagnetic substances.

    Yet we can make any of them repel or attract.

    However on a subatomic level, nothing actually attracts. Things can cause a lack of repulsion and get pushed together. Things can cause a block to ambient radiation and get pushed together. However nothing exists that can attract.



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  10. #9  
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    Quote Originally Posted by Cold Fusion
    And if it is alloyed with iron it can only attract, right?

    Well, I guess I'll get to it. Essentially, when I dropped the aluminum on my neodymium magnet, the aluminum was "buffered" while falling, as in it acted as if it fell into a very dense liquid. When I pulled it out of the field it resisted, again as if in a dense liquid. The only explanation I have for this is that eddy currents form due to the movement of the aluminum inducting current by passing through the magnetic field. This would create a form of neutral repulsion and attraction.

    What do you guys think of this? It funny that through none of the advanced physics courses I took in high school they mentioned this effect.
    This effect has something to do with Electro-magnetic induction.
    When an aluminium rod ,for example, is moving with non-zero velocity with its length cutting lines of force of a non- uniform magnetic field perpendicularly, a force acts on it due to change in flux. this is explained by Faraday's Law of EMI and Lenz's Law
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    Yes, that is the kind of behavior you would expect from the eddy current effect; i.e. the damping force would be proportional to the speed of the metal through the magnetic field.

    In the article I referenced above on the electric meter, it explains that they use a permanent magnet which exerts an opposing force proportional to the speed of rotation of the disc. This causes the disc to rotate at a speed proportional to the power being used.
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    Good, I needed clarification on that. My friends went ballistic when they moved the aluminum through the field.....,"Cold Fusion! You discovered a property of the universe!!!". That would be nice, but its highly unlikely that such a simple thing could be discovered by me first. Hmmmmm...I need a larger magnet.
    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

    "Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence"

    -Einstein

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  13. #12  
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    Quote Originally Posted by Cold Fusion
    Good, I needed clarification on that. My friends went ballistic when they moved the aluminum through the field.....,"Cold Fusion! You discovered a property of the universe!!!". That would be nice, but its highly unlikely that such a simple thing could be discovered by me first. Hmmmmm...I need a larger magnet.
    This animation below, is just a two dimensional view of some of the ambient radiation that is effected by common magnets. In reality there is a bunch more ambient radiation that I cannot draw in there, passing through the magnets in straight lines. Not even effected by the magnets.

    But the lines of ambient radiation (Free electrons moving very quickly) are representative of ambient radiation and how some of it is effected by the magnet.

    http://www.Rockwelder.com/Flash/Magn...MagnetsHow.htm

    This is how I was taught magnets are repelled in all the ways they move. Because there is no such thing as attraction in our universe. Just the appearance of attraction.

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  14. #13  
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    William, no offense, but, why do you think ambient radiation is behind every phenomenon in physics?
    Do you know what ambient radiation is? If you do, please explain
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    I thought of another reason why this could happen; in copper, when you pass an electromagnetic field through it, current is generated readily. While copper has very low electrical resistance (16nohms), aluminum has a much higher resistance (26nohms). Could it be that you are "feeling" the resistance of the electrons to move and form a current? [/tex]
    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

    "Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence"

    -Einstein

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  16. #15  
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    No. It can't be explained like that. Believe me, you have to read about Electromagnetic induction.
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  17. #16  
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    Quote Originally Posted by Cold Fusion
    I thought of another reason why this could happen; in copper, when you pass an electromagnetic field through it, current is generated readily. While copper has very low electrical resistance (16nohms), aluminum has a much higher resistance (26nohms). Could it be that you are "feeling" the resistance of the electrons to move and form a current? [/tex]
    I believe you have something there. Aluminum is faster to raise in voltage on the area the voltage is applied. Much faster then copper, because copper carries away an abundance of electrons before raising in voltage to slow the flow. That is why it conducts.

    So if you have a portion of the aluminum that quickly raises in voltage to match the source of the voltage you should get a repulsion more quickly and more powerfully then copper.

    If the copper carries away, or carries electrons to, the similarity of an abundance or shortage of electrons, there will be much less repulsion.
    Just like north and south pole magnets in the three ways they can interact. Copper tends to take on the opposite pole better then aluminum.

    That is why aluminum can be very dangerous.



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  18. #17  
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    Additionally, all conductors exhibit an effective diamagnetism when they move through a magnetic field. The Lorentz force on electrons causes them to circulate around forming eddy currents. The eddy currents then produce an induced magnetic field which opposes the applied field, resisting the conductor's motion.
    http://en.wikipedia.org/wiki/Diamagnetic

    This settles it.

    Notice the levitating frog :-D
    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

    "Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence"

    -Einstein

    http://boinc.berkeley.edu/download.php

    Use your computing strength for science!
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  19. #18  
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    No reaction with a static field except that any current flowing in the aluminium is deflected slightly..Hall Effect.

    An alternating field will induce currents which will in turn produce an alternating magnetic field. You can levitate or propel aluminium plates in alternating fields..linear motor.
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    Quote Originally Posted by Pumblechook
    No reaction with a static field except that any current flowing in the aluminium is deflected slightly..Hall Effect.

    An alternating field will induce currents which will in turn produce an alternating magnetic field. You can levitate or propel aluminium plates in alternating fields..linear motor.
    You can also cause aluminum to move closer to the magnet as well.

    http://www.Rockwelder.com/WMV/AlumEl...tromagent.html

    This shows clearly that aluminum can be caused to move towards an electromagnet. The washer is being pressed to the magnet by ambient radiation.

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    William McCormick
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