A magnet is an article that shows signs of a strong magnetic field and attracts materials like iron towards it. IT comprises two opposite poles namely North Pole (N) and South Pole (S). The most general principle of magnets is that two magnets attract each other when their opposite poles come closer and repel each other if their same poles come closer.
The Generation of Magnetic Field
The area surrounding the magnet is known as a magnetic field which has a north side as well as a south side. The magnetic field is strongest where the lines of force are closer and is weakest where the lines of force are far apart. A magnetic field consists of imaginary lines arising from moving electrically charged particles.
Concept of Magnetism
Magnetism is a phenomenon that arises from the force between two magnets or objects that either attract or repel each other. All materials on this Earth experience magnetism but the only difference is that some experience it more than others. Permanent magnet made of iron experiences the strongest effect which is also known as ferromagnetism. This form of magnetism is the strongest to be felt. Paramagnetism is the other form of magnetism in which only some materials are attracted by a magnetic field. On the other hand, diamagnetism is the form of magnetism in which materials are repelled by a magnetic field.
Materials that are not affected by magnetic fields are named non-magnetic substances. Examples of such substances are copper, aluminium, plastic, and gases but pure oxygen contains magnetic properties when it is cooled to a liquid state. The magnetic state of a material depends on various factors such as temperature, pressure, and applied magnetic field. Therefore, a material may exhibit more than one form of magnetism.
Uses of Magnetism in Our Daily Lives
Magnets can be seen in different walks of daily life including magnetic audio and videotapes, hard drives of computers, loudspeakers, electric motors, generators, washing machines, door hinges, blenders, CD players, car doors, TVs, loudspeakers, refrigerators, elevators, escalators, fax machines, toys and many more. Large cranes used in the construction industry have powerful electromagnets that are used for moving iron and steel. In addition, the credit cards also contain magnetic strips that enclose important financial information. Earth is also a huge magnet. The North Pole and the South Pole are the two areas of the earth where its attraction is largest.
Magnets are also present in some medical equipment including X-rays and MRI machines. Powerful magnetic fields are used in MRIs for charging the protons present in the human body. Some doctors also recommend magnetic therapy for the treatment of various diseases such as poor blood flow, arthritis, and many more. In this therapy, patients wear magnets in their shoe insoles, necklaces,s, and wrist bracelets.
There are many jobs that are impossible without a magnet. Some of them are given below:
– When a veterinary doctor wants to remove metal objects from the stomach of animals
– Scrapyard operators use magnets for lifting heavy objects such as cars and refrigerators
– Magnetic machines are used at airports to find metal objects under clothing and in the luggage
– For separating metallic and non-metallic objects at the junkyard
– For controlling the speed of roller coasters
Conveyor belts used at scrap yards contain magnets. These belts are used to separate metals from plastics
Maglev trains use two opposite magnets that cause it to float and makes them extremely fast and manoeuvrable
