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A magnetic Mystery

  1. Mar 30, 2007 #1
    There are two magnets stuck together through magnetic force but there is a pane of glass seperating them, when I spin the magnet closest to me clockwise, both of the magnets spin and move to the right and down, when I spin them anti-clockwise, they spin and move to the left and down.

    The magnets are side by side, and the force applied to make the magnets spin is irrelevant since I have spun them in different ways and from different angles and the result is always the same. They also spin in perfect sync.

    Could someone please summarise the forces involved that make the magnet either shift left or right in both scenarios, I'm pretty sure I already know the answer, but one of my friends disagrees.

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    Last edited: Mar 30, 2007
  2. jcsd
  3. Mar 30, 2007 #2


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    Staff: Mentor

    Pretty picture. Say, when you put these two magnets down on the same side of a flat wood table, how do they orient themselves? Where are their poles?
  4. Mar 30, 2007 #3

    The poles are present in the middle of the magnet, as opposed to the ends.
  5. Apr 3, 2007 #4
    This happens because the weight of the magnets cause more pussure on the glass at the bottom of the magnets, and less at the top. So the magnets on the glass are ever so slightly like this: magnet--> \ | / <--other magnet, and glass in the middle. That explains why it goes sideways, why it goes down, I think is much more complicated, but it's simular to the gyroscopic effect, deals with the molecular spring effect, the compression, and decompression of it. If you really want me to figure that out I could. here's what I think of the gyro effect.
  6. Apr 3, 2007 #5
    It is a simple matter of the magnetic field surrounding the magnets. If you take the average distance between parts of the magnet, you can easily compare how much magnetic force there is going to be. With the magnets parallel, the middles are only separated by the thickness of the glass, while the tips are only separated by a short distance (looks to be about one inch) If one magnet were to turn, but not the other, and the magnets were to become perpendicular to each other, the middles would still be separated only by the thickness of the glass, but the ends would be much farther apart. This would give the magnets a higher potential energy, but most things in physics tend to favor a lower state of potential energy, so the magnets spin in sync. To explain the going sideways, it is because the magnets are angled as mentioned in Brock's post, this means that the pivot point for the rotation is in a state of constant change while the magnets are spinning. This causes them to "walk".

    I hope this helps clear things up.
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