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Demagnetizer and a magnetizer

  1. Dec 5, 2007 #1

    Can someone please tell me how does a demagnetizer and a magnetizer works, I want to build a simple one, I can’t find a darn thing on google?

    I just want to magnetize a piece of nail with a machine for leaning purpose on magnets and then I want to demagnetize it without heating the piece of nail with a blowtorch to 1700 deg

    This machine and magnets won’t be used for terrorist acts

  2. jcsd
  3. Dec 5, 2007 #2


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    You need to create a solenoid. Get acquainted with Lenz's law and a few other things pertaining to magnetism (any A-Level physics book will contain those things).

    Just take copper wire, and coil it around a paper tube of the diameter you need. You then need an alternating current source, or alternating movement.

    Let's say you have a 9V battery attached to a coil wrapped around a paper tube (use a resistor in series with this or prepare for fire!).

    You want to demagnetize a nail. You can use a constant DC current and move the nail in and out of the paper tube to simulate alternating magnetic fields, or you can provide alternating current. That, is as simple as using a "push to make" or "push to break" switch in the circuit, placing the nail in the paper tube and attempting to see how long it takes to contract arthritis.

    Either way, you want the magnetic "grains" to line themselves up uniformly, for a magnetised object, and to demagnetise, you need to throw them out of order.
  4. Dec 5, 2007 #3
    dst, can I use this method or some method to build a permanent magnet motor that has a higher output then input, like a working over unity device, most of my ideas cancel its other out
  5. Dec 5, 2007 #4


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    No, not at all.

    Again, Lenz's law - only a change in energy can do useful work. God hates us.
  6. Dec 5, 2007 #5
    Rolmao, no $**t man, he really does hates us
    Last edited: Dec 5, 2007
  7. Dec 6, 2007 #6
    Go to the local hardware store and buy a screwdriver magnetizer/demagnetizer. If you're gonna invent over unity, you'll need a lot of magnetized nails.
  8. Dec 6, 2007 #7
    Man, you’ll make my day if u can point me out to even one working over unity device.
  9. May 6, 2009 #8
    Free energy.
    Last edited by a moderator: Sep 25, 2014
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