Bar Magnets

Bar Magnets

Bar magnets are narrow, rectangular pieces of ferromagnetic material or composite that generate a magnetic field. They are permanent magnets, meaning they don't need constant electric current to retain their magnetism, and they have a smooth and uniform cross section and surface. Usually made from iron or steel, bar magnets have a south and north pole on each end, and are the most common type of magnet shape. They are used to pick up small metallic objects like metal shavings or nails and screws, as magnetic stirring rods in laboratory applications, and as magnets on refrigerators. Their most common application is the needle used in compasses. The north pole of the bar magnet aligns with the actual north pole, letting travelers know what direction they are headed.

The magnetic lines of force form closed, continuous lines on either side of the bar magnet. They never intersect, and flow from north to south in direction. When cut in half, a bar magnet automatically forms into two separate magnets, each with their own poles and magnetic field. The average magnetization magnitude of bar magnets is 100,000 A/m, but this varies based on what type of ferromagnetic material is chosen. When using any type of magnet, especially bar magnets that are often found in homes, it is important to keep them away from any sort of electronic device, including speakers, televisions and radios. Irreversible damage can occur to the data storage if it comes in contact with a magnet, even if it has a weak magnetic force.