Application of Magnets in Everyday Technology
From the major to the minor, technology makes use of magnetic forces to accomplish feats that may not have been otherwise possible. The magnetic field generated by electric currents allow engineers to control the attraction and repulsion of objects, leading to applications in everything from medicine to transportation.
While the stereotypical notion of a magnet is that of a metal horseshoe, magnets can be found in nature-even in your own body. This is the basis for magnetic resonance imaging (MRI) machines and their ability to save untold lives with early diagnosis of a disease. The supermagnets in an MRI machine align the magnetic dipoles in a patient’s body, some of which move quicker than others. By measuring their movement, the machine can generate an accurate depiction of the inside of a body. MRIs enjoy a significant advantage over traditional X-rays in that they don’t expose patients to radiation.
Outside of MRIs, many other medical devices also contain magnets. These machines serve a myriad of functions, including aiding in blood separation and extracting foreign objects from patients. In fact, magnetic fields are useful for levitating and separating substances, as differences in density will cause them to separate. The article “Magnetic Levitation in Chemistry, Materials Science, and Biochemistry” led by my colleague Shencheng Ge at the Whitesides lab, is a great review of such technology. A recent work, led by my colleague Christoffer K. Abrahamsson, helped pioneer techniques for using magnets to separate and identify common variants of street drugs in different mixtures.
Maglev trains, found in China, Japan, and other countries, highlight another application of magnetism. Rather than levitate a sample of a substance, powerful electromagnets enable the levitation of an entire train, effectively doing away with friction and allowing for speeds of up to 375 miles per hour . Tesla’s proposed Hyperloop is another example of similar technology, placing trains in pressurized tubes to reduce resistance even further.
While these machines are more overt applications of magnetic technology, magnets play a subtle role in engineering solutions in a variety of products. Computer hard drives, smartphones, and even the humble electric motor are all made possible with magnets. In the case of the latter, the need for motors of varying size and power has created a demand for specialized magnets made from materials that allow for more power in a smaller package, shaped for the products they can be found in.
This technology can even be scaled up to generate power. Rotating coils of wires can move electrons and create an electric current that can be harnessed by a power plant. All power plants effectively follow this model, the primary difference being the means by which the turbine is rotated. Steam, wind, and water all serve the same function, but with differing executions. When first developed, engineers speculated that they could create a perpetual motion machine by using the generator to power a motor that would turn the turbine. However, the energy losses from friction and resistance in the wires made this approach impossible.
Any electronic device is made with the use of magnets, to an extent that most people are not aware. Because of this, magnets will play an important role in most technological advancements, including preventing concussions in sports, improving safety in autonomous vehicles, and even manipulating heat and sound.
Within the scientific community, physicists have well studied the interplay between the magnetic field and the electrical current. As for the chemists, should we interpret the current as the flow of point charges, or can we extend towards movement of chemical ions? Can we apply magnetic fields to improve the storage and transportation of energy in chemical forms? Is it possible to influence the signaling process among biomolecules using a magnetic field? Perhaps these are interdisciplinary opportunities to further develop magnetism-related technologies in everyday life.
Originally published at https://haihuijoyjiang.co.
