Mystery of Magnetism
- Dayah Sokolov
- Aug 12
- 4 min read
Audience: Middle and High School Students
Have you ever held a magnet up to your fridge and felt the tension between two identical magnetic poles? That invisible push or pull comes from the magnet’s magnetic field. While most people are familiar with magnets, fewer understand the fascinating science behind them. At the rudimentary level, a magnet is an object or material that produces a magnetic field. The magnetic field is generated by the movement of electrons, which are tiny subatomic particles that orbit the nuclei of atoms. This field is what allows magnets to attract certain materials, such as iron, and repel other magnets depending on the position of their poles. In most materials, these electron movements are random and cancel each other out. However, in magnetic materials, many of their electrons spin in the same direction, which causes their magnetic fields to align and creates a larger more powerful magnetic force.
There are several types of magnets and each one functions in a slightly different way. Permanent magnets are materials that generate their own constant magnetic field. These are typically made from metals such as iron, cobalt, or nickel. Once magnetized, permanent magnets remain magnetic for centuries without needing any additional energy input. The magnetic properties of permanent magnets are built into the structure of the material itself, making these magnets useful in countless applications like computers, speakers, and motors.
On the other hand, some materials can become magnetic temporarily. They are not naturally magnetic, but can become magnetized when exposed to a strong external magnetic field. However, this magnetism disappears once the external magnetic field is removed. These materials are classified as temporary magnets and they are useful in situations where a magnetic effect is only needed for a short period. Some examples of temporary magnets are paper clips and iron nails.
The third most common type of magnet is the electromagnet. Unlike permanent magnets, electromagnets only exhibit magnetic properties when an electric current is flowing through them. Electromagnets are usually made by wrapping a coil of wire around a metal core, and when electricity passes through the coil it generates a magnetic field. This type of magnet can be turned on or off simply by starting or stopping the flow of electricity, which makes electromagnets incredibly useful in various machines and electronics. Some examples of machines where electromagnets are used are generators, washing machines, and MRI machines.
Interestingly, the Earth itself acts like a massive magnet. Deep within the planet, molten iron and other metals move in swirling patterns inside the outer core. This movement creates a magnetic field that extends far into space. The Earth’s magnetic field is crucial for life on the planet, as it protects us from harmful solar radiation by deflecting charged particles emitted by the Sun. Without this protective shield known as the magnetosphere solar radiation could strip away our atmosphere and make Earth uninhabitable. Furthermore, the magnetosphere plays an important role in navigation. Many animals, like birds and sea turtles, use the Earth’s magnetic field to navigate through their long migrations. According to The Lohmann Lab at The University of North Carolina at Chapel Hill, “in the case of sea turtles, magnetic map information can be used either to guide a turtle toward a particular area or to help it assess its approximate location along a transoceanic migratory route.” However, at this time scientists do not know exactly what mechanisms allow animals to identify magnetic fields.
In today’s world, magnets are everywhere. They are used in an enormous variety of technologies and devices that we often take for granted. For instance, magnets are essential in electric motors, which power everything from household appliances to cars. They are also found in computer hard drives, where they help store vast amounts of digital data. In relation to smartphones, magnets are used in their speakers, vibration motors, and even in the mechanisms that allow phone cases and chargers to snap into place. One of the most impressive uses of magnets is in maglev trains, short for magnetic levitation. These high-speed trains use powerful magnets to lift and propel the train above the tracks, eliminating friction and allowing for incredibly fast and smooth travel. Another vital application is in the field of medicine. MRI machines, also known as Magnetic Resonance Imaging machines, use strong magnetic fields to create detailed images depicting the insides of the human body. This non-invasive technique allows doctors to diagnose injuries and diseases with great precision, all without the need for surgery.
Magnets are also playing an increasingly important role in the future of green energy. They are used in wind turbines to generate electricity and in electric vehicles to power motors without the need for fossil fuels. As technology advances and the world moves toward more sustainable solutions, magnets will remain at the forefront of innovation. From clean energy to cutting-edge transportation and life-saving medical equipment, magnets are a key component in many of the tools shaping our future. So to conclude, magnets are more than just interesting objects stuck to our refrigerators. They are powerful tools grounded in fascinating science, with wide-ranging applications that affect nearly every aspect of modern life. Whether in everyday gadgets, advanced scientific instruments, or technologies of the future, magnets continue to play a critical role in how we live, move, communicate, and heal.
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