A magnet attracts certain objects due to the presence of positive and negative magnetic charges in these objects. Ferromagnetic materials, such as iron, have aligned magnetic domains that strongly react to magnetic fields. On the other hand, non-magnetic objects do not possess this property and are therefore not attracted to the magnet.
Some materials are naturally sensitive to magnets, but not all of them, far from it! This attraction mainly depends on their ability to become small temporary or permanent magnets themselves by reacting to a magnetic field. Certain elements like iron, nickel, or cobalt are said to be ferromagnetic: their atoms behave like mini-aligned magnets that collectively strengthen their magnetization. Other materials, such as aluminum or copper, have such weak reactions that you will hardly notice any attraction; they are then said to be paramagnetic or diamagnetic. In fact, the trick lies mainly in how electrons orbit around the nucleus of the atoms: this movement creates tiny electric currents that generate magnetism on an ultra-small scale. The internal organization of each material makes all the difference!
On a small scale, everything is a matter of atoms and especially electrons. These tiny particles orbit around the nucleus of the atom, and by moving, they create tiny magnetic fields like mini-magnets. Often, these mini-magnets cancel each other out because their orientations are completely opposite. But in certain materials (like iron, cobalt, or nickel), groups of atoms naturally start to align their magnetic fields in the same direction: this is called a magnetic domain. If all these domains align — because they are influenced by a powerful magnet, for example — the material becomes magnetic and starts to attract or repel nearby metallic objects.
The magnetic force felt by an object varies greatly with distance. The farther away the object is, the more this force decreases rapidly: within a few centimeters, you lose a lot of attraction strength. Orientation also plays a role: you have probably noticed that two magnets attract each other strongly when they are face to face, but hardly move when placed side by side or in a weird position. This is because the magnetic field lines directly influence the felt force, depending on how the poles of the interacting magnets are positioned relative to each other. In practice, you therefore get the maximum magnetic power when your objects or magnets are close and properly aligned.
The temperature directly affects the agitation of a material's atoms, and it also disrupts its magnetic properties. When a magnet is heated, its magnetic domains move more and more due to thermal energy. Beyond a certain critical temperature, known as the Curie temperature, the agitation becomes so intense that the domains become completely disorganized. As a result, the magnet completely loses its attractive power. For example, iron becomes non-magnetic around 770°C. Cooling the material can restore its magnetic properties, but sometimes not as strongly as before.
If you heat a magnet strongly, it will gradually lose its magnetism; this thermal limit is called the 'Curie temperature'.
Despite their intriguing name, superconductors are capable of completely expelling a magnetic field thanks to the Meissner effect, allowing them to levitate above a magnet!
Animals like pigeons, sea turtles, and bees possess a magnetic sense thanks to tiny crystals of magnetite present in their bodies, allowing them to navigate easily during their movements.
The Earth's magnetic field protects our planet from solar wind, a stream of charged particles emitted by the Sun. Without this natural magnetic shield, there would likely be no terrestrial life as we know it today!
A magnet has two poles: north and south. When two identical poles (north-north or south-south) are brought close together, the magnetic field lines collide and generate a repulsive force. In contrast, two opposite poles (north-south) create an attraction because the magnetic lines can easily connect.
The attractive force of a magnet primarily depends on three factors: the ferromagnetic nature of the target material, the distance between the magnet and the object, and the orientation of the magnet and the object. The closer the distance and the more favorable the orientation, the stronger the attraction.
No, only certain metals, mainly those that are ferromagnetic such as iron, nickel, cobalt, and some specific alloys, are attracted to magnets. Metals like aluminum, copper, or gold, for example, are not attracted because their internal structures do not allow magnetic domains to align.
Yes, it is possible to temporarily or permanently induce magnetic properties in certain materials by aligning their magnetic domains using a powerful magnetic field. Conversely, heating a magnet beyond a certain temperature (the Curie temperature) causes its magnetic properties to vanish, as this disrupts the alignment of the internal magnetic domains.
Only certain materials, known as ferromagnetic materials (such as iron, cobalt, or nickel), contain atoms whose magnetic domains can align under the influence of a magnetic field. Materials like wood, plastic, or glass do not have this specific atomic structure, which is why they are not attracted to magnets.
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