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I have some very basic knowledge in magnetics:

  1. I know ferro- and neodymium magnets
  2. I know there are two poles of magnets (North and South)
  3. Magnets to magnets connections are strong pulling (in case different poles) and strong pushing (same poles)
  4. Magnets to metal connections are medium pulling (no matter of poles)

I bought some neodymium magnets, and played with it a bit. I have a smartwatch, and its back is somewhat super-strange for me:

  1. My neodymium magnet's one pole (I couldn't distinguish which one, let's say Northpole) pulls the watch's center very strongly
  2. The magnet's South pole pushes the center of the watch, and squeezes towards the circumference of the watch (with not-so-strong pulling)
  3. The watch itself is not magnetized, at least it doesn't pulls any metal thing, only other magnets.

How can the watch pulling only one pole of my magnet if the watch itself is not a magnet?

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    $\begingroup$ Can you do these push pull experiments with a big time-gap? Just to make sure that permanent magnet does not magnetize the watch. Can you get something like a compass to really make sure the watch is not magnetized by the permanent magnet? Or perhaps watch is weakly magnetic anyway $\endgroup$
    – Cryo
    Jul 6, 2022 at 15:39

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This watch could be using something called a Halbach array. Halbach arrays can change the magnetic field so that one pole has much more magnetic field than the other. Here are some links to some information about this, Halbach arrays, Halbach Arrays 2.

This arrangment of magnets can also greatly reduce the reach of the magnetic field which might explain why it doesn't feel like it is attracted to anything metal. If this watch uses wireless charging this halbach array might be used to align the coil inside it with the coil in the charging base.

I hope that this information helps. There are so many smart watches out there with so many different designs.

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