Many of us may know the term magnet, but what are they exactly? They are objects that create a field, which cannot be seen, and attracts materials with ferromagnetic substances, such as iron. Magnets attract other materials, and they attract and repel magnets as well. While liquid substances containing ferromagnetic material may be magnetized when close to a magnetic field, solid materials are the most common objects to be magnetized. The liquid containing ferromagnetic particles are known as ferrofluid. Although non-ferromagnetic materials will create some type of response to magnetic fields, they are not strong enough to be referred to as magnetic.
Usually magnets their own magnetic field whether or not other fields are present; these magnets are referred to as permanent magnets. They contain material like iron, nickel, and cobalt, and some contain minerals like lodestone, which is magnetized instinctively. However, ordinary permanent magnets are made when strong magnetic fields are applied to ferromagnetic materials. This substance can be either soft or hard. The soft matter like annealed iron must be close to other magnets, or they will lose their magnetic field rapidly.
The primary cause for the invention of magnets were to assist in navigation. Many people think of compasses, refrigerator magnets, and other magnetized material when the term magnet is brought up. There are many uses for magnetized materials nowadays. Magnetic tape is a common item that people use everyday for credit cards and ATM cards. Computers also use magnetic items, such as hard disks, which are surrounded by magnets, microphones and speakers. Generators, transformers, and places like hospitals can examine organs via magnetic resonance imaging. Like other technological advancements, there may be risks, but the medical, educational, and other various uses of magnets undoubtedly assist society.