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Compass Needles

  1. Nov 11, 2012 #1


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    I was wondering that if a compass was left on a horizontal angle for billions of years, would the north and South Pole needles eventually rip apart due to the north needle being repelled from the south needle, and vice versa, or could the magnetic field of either needle block the magnetic field of the alternative, repelling pole?
  2. jcsd
  3. Nov 11, 2012 #2


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    The strength of the Earth's magnetic field is too small to have any effect like what you are suggesting.

    It's like an ant pushing on a house over billions of years. It's not that the any has a tiny effect, it's that it has ZERO effect because it cannot to any extent overcome the forces holding the house on its foundations.
  4. Nov 11, 2012 #3

    Vanadium 50

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    Besides, the north and south poles of a magnet do not repel.
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