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Field lines goes from south to north. When thinking of charge instead of "south" and "north", we can say that south pole is positively charged and north pole is negatively charged. So positive charges move toward negative charges.

enter image description here

But a paramagnet is attracted to both pole (south and north or more conventionally positive and negative charges). My question is why paramagnet is attracted to both pole? Paramagnet has less unpaired electron than ferromagnet. Is that the reason? Cause paramagnet behaves like they are positively and negatively charge simultaneously. But their charges is soo less that's why they stay together and attracted to magnetic poles very weakly.

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Paramagnets do not retain any magnetization in the absence of an externally applied magnetic field because in the main thermal motion randomizes the spin orientations. So paramagnets are not magnetised when the applied field is removed. An external field will induce magnetism with a north pole induced at the side nearer the inducing south pole, and vica versa for an induced south pole, and thus a net attraction occurs irrespective of the pole of the inducing magnet.

Your image illustrates the same effect for iron filing which are classed as made of a soft magnetic material in that iron does not retain much of a magnetic field after the external inducing field has been removed. which are ultimately responsible for their magnetic properties

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  • $\begingroup$ One could compare paramagnet to chess-board. I don't know if chess board is paramagnet. I watched in a video that paramagnets attract to south and north pole both (weakly). And the same thing happens to chess-board. But my question was why chess-board (paramagnet) is attracted to both pole? $\endgroup$
    – Man
    Jan 29, 2022 at 14:52
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Actually both paramagnets and ferromagnets behave in that way: they are attracted by both poles because each of the magnetic dipoles inside the material behaves like a compass and can then rearrange itself accordingly to an external magnetic field (here generated by the poles). When the majority of these compasses aligns, the net effect of this collective alignment is the appearance of a macroscopic magnetic field, that points in the same direction as the external field and causes the attractive force.

The difference between paramagnetic and ferromagnetic materials is:

  • the order of magnitude of the force they feel when in a magnetic field;
  • the possibility for the ferromagnets to keep some magnetization even when the external magnetic field is removed.

This magnetization is though temporary as the ferromagnet will return to its normal "neutral" state after a while, unless it undergoes repeatedly an hysteresis cycle to become a permanent magnet: the external magnetic field is swept back and forth and every time a fraction of the dipoles are "convinced" to align with the majority. At this point, when (almost) all of the dipoles are aligned, they are locked into place: it would require quite some energy for any of them to point up if all its neighbors point down.

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  • $\begingroup$ One could compare paramagnet to chess-board. I don't know if chess board is paramagnet. I watched in a video that paramagnets attract to south and north pole both (weakly). And the same thing happens to chess-board. But my question was why chess-board (paramagnet) is attracted to both pole? $\endgroup$
    – Man
    Feb 14, 2022 at 12:10
  • $\begingroup$ To me it sounds like you are referring to ferrimagnets (the "i" is not a typo!) or to antiferromagnets, which are a particular case of ferrimagnets. In these materials the magnetic dipoles are alternated in opposite directions like the black and white squares in a chess-board. The figure and the video in en.wikipedia.org/wiki/Antiferromagnetism should be helpful to visualize. $\endgroup$
    – Luca M
    Feb 19, 2022 at 11:55
  • $\begingroup$ As for why attraction happens to both poles, the dipoles in the material align in the same direction as the field you put them in: if you put your material near the S pole of the magnet, it will (temporarily) become itself a sort of a magnet with its N pole facing the S pole of the magnet, generating attraction between the material and the magnet. The viceversa happens if you move it close to the north pole, and you will still have attraction. Last thing: dont think of magnetic phenomena in terms of charge because it is not what physically happens and can lead you to some conceptual errors :) $\endgroup$
    – Luca M
    Feb 19, 2022 at 12:00

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