In nature, there are some materials that, in the presence of a magnetic field, become magnets weak or not. These materials are classified into ferromagnetic, paramagnetic and diamagnetic.
Paramagnetics
They are materials that have electrons unpaired and that, in the presence of a magnetic field, align themselves, giving rise to a magnet that has the ability to cause a slight increase in the strength of the magnetic field value at any point. These materials are weakly attracted to magnets. These are paramagnetic materials: o aluminum, O magnesium, O copper sulfate etc.
Copper Sulfate, a paramagnetic material
Diamagnetic
They are materials that, if placed in the presence of a magnetic field, have their elementary magnets oriented in the opposite direction to the applied magnetic field. Thus, a magnetic field is established in the substance that has a sense opposite to the applied field. They are diamagnetic substances: o bismuth, O copper, a silver, lead etc.
Bismuth crystal, a diamagnetic material
Ferromagnetics
The substances that make up this group have very different characteristics from paramagnetic and diamagnetic materials. These materials magnetizeup strongly if placed in the presence of a magnetic field. It is possible to verify, experimentally, that the presence of a ferromagnetic material strongly alters the value of the magnetic field strength. Are ferromagnetic substances only the iron, O cobalt, O nickel and the alloys that are formed by these substances. You Ferromagnetic materials are widely used when one wants to obtain high intensity magnetic fields.
Cobalt, a ferromagnetic material
Ferromagnetic substances are strongly attracted to magnets. The paramagnetic and diamagnetic substances are, in most cases, called substances not magnetic, as their effects are very small when under the influence of a field. magnetic.
By Marco Aurélio da Silva
Brazil School Team
Source: Brazil School - https://brasilescola.uol.com.br/fisica/materiais-paramagneticos-diamagneticos-ferromagneticos.htm