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Does a permanent magnet looses its magnetism?

  1. Jul 20, 2014 #1
    The question is slightly deceiving however still simple for those academics therefore, here I present my question:

    If I take a para-magnetic material and put it very close to a homogeneous magnetic field, the para magnetic material will start to accelerate towards the magnetic body thus it has kinetic energy (but I ensure it does not hit the magnet and stop it with my fingers) so does the magnetic field or body loose it magnetism or will the same magnetism stay? Because in Wikipedia, it says:

    Energy is needed to generate a magnetic field both to work against the electric field that a changing magnetic field creates and to change the magnetization of any material within the magnetic field
    However I'm sure that para-magnetic materials are not magnetized, so where is this energy coming from? Or is my understanding wrong if so can someone link me to a good website which uses mathematics and theory to show how para magnetic material works?

  2. jcsd
  3. Jul 20, 2014 #2


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    2017 Award

    Staff: Mentor

    In a homogeneous field, the paramagnetic material does not move - why should it?
    An acceleration towards permanent magnets just happens as their field is not homogeneous. You (partially) align the magnets in the paramagnetic material with the magnetic field and bring them closer together, this releases energy.
    If you want to separate the objects again, you have to put in energy.
    They get magnetized by your permanent magnet.
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