What happens to the domains in this iron nail when the south pole of a magnet approaches it from the top?

The characteristics of the poles of the magnets allow to find the correct result for the question about where the arrows of the magnetic domains point is:

      A) The arrows align to point up.

The lines of magnetic induction are drawn leaving the North Pole towards the South Pole, the magnetic force is in this same direction.

Magnetic domains are regions within matter, with a single magnetic moment, in magnitude and direction, the number of magnetic domains is defined by the decrease in the total energy of the system.

They indicate that the south pole of the magnet approaches the nail, therefore the different magnetic domains, you feel the attraction force of the same. In general, the point of the arrows is the North Pole.

Therefore the different arrows begin to point upwards as they are attracted to the South pole of the magnet.

In conclusion, using the characteristics of the poles of the magnets we can find the correct result for the question about where the arrows of the magnetic domains point is:

       A) The arrows align to point up.  

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