Engineering
Superconductors make highly efficient electronics, but the ultralow temperatures and ultrahigh pressures required to make them work are costly and difficult to implement. Room-temperature superconductors promise to change ...
Mar 28, 2023
0
6
Engineering
A new study shows how a magnetic material can be used to help monitor the amount of life left in a rechargeable battery before it needs to be recharged.
Jun 14, 2022
0
11
Robotics
When you hear the term "robot," you might think of complicated machinery working in factories or roving on other planets. But "millirobots" might change that. They're robots about as wide as a finger that someday could deliver ...
Sep 14, 2022
0
55
Engineering
Borrowing a technique from inkjet printers, researchers at Princeton Engineering have rolled out a pixel-by-pixel method to program and manufacture soft structures for use in robotics, biomedical devices or architectural ...
May 24, 2022
0
113
Electronics & Semiconductors
A research team from Northwestern Engineering and the University of Messina in Italy have developed a new magnetic memory device that could lead to faster, more robust Artificial Intelligence (AI) systems. Composed of antiferromagnetic ...
Jun 23, 2021
0
170
Electronics & Semiconductors
Researchers are a step closer to realizing a new kind of memory that works according to the principles of spintronics which is analogous to, but different from, electronics. Their unique gallium arsenide-based ferromagnetic ...
Nov 30, 2020
0
162
Energy & Green Tech
An increasing number of electric cars are being sold, consequently raising the quantity of produced electric motors. At the end of their useful life, these electric motors are shredded and then recycled. The individual components ...
Jan 2, 2024
0
15
Engineering
Magnetic materials pose major limitations in power electronic applications at high frequencies, but MSE Professor Michael McHenry and alums Paul Ohodnicki, Alex Leary and Sam Kernion have made advancements on materials and ...
Sep 14, 2021
0
7
Robotics
The rhythmic motions of hair-like cilia move liquids around cells or propel the cells themselves. In nature, cilia flap independently, and mimicking these movements with artificial materials requires complex mechanisms. Now, ...
May 19, 2021
0
5
Energy & Green Tech
The future of faster, more efficient information processing may come down to light rather than electricity. Mark Lawrence, a postdoctoral scholar in materials science and engineering at Stanford, has moved a step closer to ...
Jul 24, 2019
0
13
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
