Image: MagnetEZ

Description: A "horseshoe" magnet made of Alnico, an alloy of iron, aluminum, nickel, and cobalt. Probably around 1 inch (3 cm) long. It is made in a "horseshoe" shape to bring the North and South poles of the magnet close together, creating a strong magnetic field between them. The metal plate between the poles at bottom is called a "keeper". It is left on the magnet when not in use, to prevent the magnet becoming demagnetized. By creating a closed magnetic circuit, it strengthens the magnetic flux in the magnet, making it harder for mechanical shocks or high temperatures to randomize the magnetic domains of the metal.
Title: MagnetEZ
Credit: the author is owner
Author: Eurico Zimbres FGEL/UERJ
Permission: Free for all use
Usage Terms: Creative Commons Attribution-Share Alike 2.0 br
License: CC BY-SA 2.0 br
License Link: http://creativecommons.org/licenses/by-sa/2.0/br/deed.en
Attribution Required?: Yes