We all have heard earth is a giant magnet, it’s true! Magnets are everywhere many electronics use concept of magnetism & they have vast range of applications from constructive purposes like converting wind energy to electricity ( windmills ) or Fan for doing exactly opposite! There are MagLev trains which work on “magnet levitation”, but on other hand they can be used for destructive purpose like EMP ( electromagnetic pulse). EMP can fry ICs in electronics and make them inoperable, mobile phones can be turned into bricks in matter of seconds!
Let’s discuss more about magnets.
There are two types of magnets –
- Permanent Magnets
Electromagnets are not permanent magnets (ie. They require constant flow of electricity to show magnetism). Very low electricity can make powerful magnets a few pencil cells (batteries) can create strong electromagnets that can lift heavy weights.
Permanent Magnets are usually the ones found in electronics like speakers and don’t require constant source of electricity to show magnetism .
There are four categories of permanent magnets –
- neodymium iron boron (NdFeB)
- samarium cobalt (SmCo)
- alnico and ceramic or ferrite magnets.
This type of magnet is composed of rare earth magnetic material, and has a high coercive force.
Coercive force – in electrical engineering and materials science, the coercivity, also called the magnetic coercivity, coercive field or coercive force, is a measure of the ability of a ferromagnetic material to withstand an external magnetic field without becoming demagnetized.
- Magnetism is used in medical field in straight applications like MRIs (magnetic resonance imaging) to weird & unproven applications like Magnetic therepy.
- Magnetic levitation Trains or MagLev trains are extremely fast and use concept of electromagnets
- In electronics like speakers, etc
- In storage devices like HDD
- Navigation (because magnets always points its north pole to earth’s south & south to north hence, it can be used to create magnetic compass)
- Recent studies show that magnets repel organic matter this can be used to create zero gravity effect
Magnetic Resonance Imaging (MRI) is a form of radiology, which uses a magnetic field scanner to detect the positively charged ions of water throughout the human body. The resulting radiographs display stark contrasts between the various soft tissues throughout the body, which has made it the preferred radiology technique for neurological and musculoskeletal imaging.
Magnetic therapy for healing has been around for centuries. Many ancient civilizations, such as the Greeks, Hebrews, Indians, Chinese and Egyptians, used magnets for medical purposes. No one exactly knows how the magnets promote healing, but it’s theorized that magnets attract metal elements in the body, such as iron in blood to increase blood circulation and therefore instigate healing.