Related topics: magnetic properties

Researchers develop new lens manufacturing technique

Researchers from Washington State University and Ohio State University have developed a low-cost, easy way to make custom lenses that could help manufacturers avoid the expensive molds required for optical manufacturing.

Transforming waste heat into clean energy

Do you feel the warmth coming off your computer or cell phone? That's wasted energy radiating from the device. With automobiles, it is estimated that 60% of fuel efficiency is lost due to waste heat. Is it possible to capture ...

Researchers modify magnetic behavior of exotic materials

People are not the only ones to be occasionally frustrated. Some crystals also show frustrations. They do so whenever their elementary magnets, the magnetic spins, cannot align properly. Cesium copper chloride (Cs2CuCl4) ...

Triplet superconductivity demonstrated under high pressure

Researchers in France and Japan have demonstrated a theoretical type of unconventional superconductivity in a uranium-based material, according to a study published in the journal Physical Review Letters.

New smart material works better under pressure

Advanced robotics sensitive touch or next-generation wearable devices with sophisticated sensing capabilities could soon be possible following the development of a rubber that combines flexibility with high electrical conductivity.

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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