Related topics: magnetic properties

Shape-encoded dynamic assembly of mobile micromachines

Field-directed and self-propelled colloidal assembly can be used to build micromachines to perform complex motions and functions, although their integration as heterogenous components with specified structures, dynamics and ...

Field-responsive mechanical metamaterials (FRMMs)

In a recent study published in Science Advances, materials scientists Julie A. Jackson and colleagues presented a new class of materials architecture called field-responsive mechanical metamaterials (FRMM). The FRMMs exhibit ...

Turning water into ice in the quantum realm (Update)

When you pop a tray of water into the freezer, you get ice cubes. Now, researchers from the University of Colorado Boulder and the University of Toronto have achieved a similar transition using clouds of ultracold atoms.

New laws of attraction: Scientists print magnetic liquid droplets

Inventors of centuries past and scientists of today have found ingenious ways to make our lives better with magnets—from the magnetic needle on a compass to magnetic data storage devices and even MRI (magnetic resonance ...

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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