For many people, magnets are a mysterious form of technology that’s hard to fully understand and comprehend.
Mastering magnetism in itself is a triumph in human invention and ingenuity as it has allowed us to implement it in a lot of inventions and use it in many different ways. From helping us navigate the world to being ever present in our technology and entertainment devices, here are the many different uses of magnetism in our society.
Compasses use magnetism to help explorers and orienteers alike stay on course and know which direction they’re traveling. These devices tap into earth’s natural magnetic field that surrounds our world and use it to guide us to exactly where we are. Since opposite attracts in magnetism, the southern pole of a compass’s needle is attracted to the naturally magnetic north pole, and it’s this that allows users to accurately discern where north is.
Magnetic sensors are a type of electrical switch which can detect when a magnetic force is near, and when one is detected, which closes the switch to complete a circuit. These are mainly used in security systems such as trip alarms and can detect when a secure door or window is being opened.
These sensors can also be used to track the positions of tools or equipment and is used a lot by the military to monitor both their own fleet as well as enemy vehicles and troops.
The storage devices used in computers and other forms of technology utilize magnetic disks to store digital data. Data is stored in binary code, which we interpret as either 1’s or 0’s. To store these, tiny areas of the magnetic disk are either independently magnetized, which stores a 1, or demagnetized, which stores a zero. The reason magnetism is used to store data is that even when the device is switched off, it continues to store this information, meaning that data is a lot harder to wipe and destroy.
When data is stored on a hard drive, it isn’t just dumped on the disk all jumbled up. Instead the data is stored in a very orderly pattern on each platter, arranged in concentric, circular paths called tracks, which is broken up into smaller areas called sectors. When data is stored, used, or deleted, a head moves over the patter, which is similar to a needle on a turntable, to read it.
Magnets are used in speakers to produce the mechanical vibration which creates sound through. This is achieved through the interaction between the magnetic field created by the pulsating electronic signals that are passing through a coil that’s suspended in another strong magnetic field. As these magnetic fields are opposite, the force created between them causes the vibrations, which in turn, creates sound. The magnets used in speakers can be really strong, too, depending on the size and quality. The most impressive of these are being found in amps as the bigger the magnet, the louder the speaker.