Magnetsen

Magnetsen are objects that produce magnetic fields and exhibit magnetic properties, such as attracting ferromagnetic materials and repelling or attracting other magnets. They can be natural, such as lodestones, or manufactured as permanent magnets or electromagnets. The defining feature of magnetsen is their ability to generate a magnetic field described by a magnetic dipole moment. In many materials, microscopic magnetic moments align in regions called domains; when these domains align collectively, the material becomes permanently magnetized.

Permanent magnetsen come in several families. Ferrite magnets are inexpensive and corrosion resistant; alnico magnets are strong and stable at high temperatures; rare-earth magnets, such as neodymium‑iron‑boron (NdFeB) and samarium‑cobalt (SmCo), offer very high magnetic strength for their size but may be sensitive to temperature or cost. Electromagnets generate a magnetic field only when an electric current passes through a coil of wire, and their strength can be adjusted by changing current or coil turns.

Common applications include electric motors and generators, transformers, loudspeakers, magnetic storage devices, and medical imaging equipment such as MRI machines. Magnetsen also enable magnetic separation, sensing, and actuation in industrial and consumer products.

Safety and environmental notes: strong magnets can pinch skin and interfere with medical implants; unusual care is required around electronic devices and around objects with sharp magnetic fields. End-of-life recycling and material sourcing are increasingly emphasized for rare-earth magnets.

Historically, the use of lodestones was documented in ancient times, leading to advances in magnetism in the 18th–20th centuries. The development of rare-earth magnets in the late 20th century significantly expanded magnet strength and applications.