Related topics: magnetic properties

Controlling self-doping in magnetite with temperature

One of the most abundant iron-containing minerals on Earth, and also the oldest known magnetic material, is magnetite, Fe3O4. Magnetite has applications in many fields, such as the study of paleomagnetism—magnetism in rocks ...

Novel semiconductor gives new perspective on anomalous Hall effect

A large, unconventional anomalous Hall resistance in a new magnetic semiconductor in the absence of large-scale magnetic ordering has been demonstrated by Tokyo Tech materials scientists, validating a recent theoretical prediction. ...

A new topological magnet with colossal angular magnetoresistance

While electrons are well known to carry both charge and spin, only the electric charge portion is used as an information carrier in modern electronic devices. However, the limits of modern electronics and the impending end ...

Magnetic symmetry is not just like looking in a mirror

When you think about how rapidly computers filled our homes, our cars and even ourselves through watches and earpieces, it might be hard to believe that there is a massive gap between computer's processing power and the speed, ...

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Magnet

A magnet (from Greek μαγνήτις λίθος magnḗtis líthos, "Magnesian stone") is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials and attracts or repels other magnets.

A permanent magnet is one made from a material that stays magnetized. An example is a magnet used to hold notes on a refrigerator door. Materials that can be magnetized, which are also the ones that are strongly attracted to a magnet, are called ferromagnetic (or ferrimagnetic). These include iron, nickel, cobalt, some rare earth metals and some of their alloys (e.g. Alnico), and some naturally occurring minerals such as lodestone.

Although ferromagnetic (and ferrimagnetic) materials are the only ones with an attraction strong enough to a magnet to be commonly considered "magnetic", all other substances respond weakly to a magnetic field, by one of several other types of magnetism.

An electromagnet is made from a coil of wire which acts as a magnet when an electric current passes through it, but stops being a magnet when the current stops. Often an electromagnet is wrapped around a core of ferromagnetic material like steel, which enhances the magnetic field produced by the coil.

The overall strength of a magnet is measured by its magnetic moment, while the local strength of the magnetism in a material is measured by its magnetization.

This text uses material from Wikipedia, licensed under CC BY-SA