Magnetic field across pole pieces...

Discussion in 'Physics' started by Externet, Oct 11, 2018.

  1. Externet

    Thread Starter AAC Fanatic!

    Nov 29, 2005
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    A magnet fitted with long, straight, parallel pole pieces; will it have a constant field between them, near or distant from the magnet ?

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    A piece of iron placed at the middle of length or placed at the far right will attach with the same strength ?
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
    15,876
    4,651
    The centre will be the area of least attraction.
    The ends will have the greatest attraction.
    All is revealed with iron filings


    Max.
     
  3. wayneh

    Expert

    Sep 9, 2010
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    I was all set with my answer but then started second guessing myself. So take my musings with a grain of salt. I was thinking the field will be strongest where there is the greatest density of field lines, and I was thinking that happens where the path length (field line length) is shortest. That would mean the ends of the magnet will have stronger field strength. But after thinking on it a bit more I think the field density is uniform across the face of the poles.
    Based on what I just said above, I believe the attraction will be basically uniform from one end to the other.

    I'm looking for an analysis of disc or "unipolar" magnets but so far haven't found much of anything useful.
     
  4. wayneh

    Expert

    Sep 9, 2010
    14,788
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    He's not talking about that kind of magnet.

    I think this may be useful:
    https://www.kjmagnetics.com/blog.asp?p=magnets-are-weird
     
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