Education

What is Magnetism? 

The ancient Greeks were first among the earliest people who observed magnetism and electricity in their natural state. The origin of the words ‘Magnetism’ and ‘Magnet’ can be sourced back to the name of a Greek tribe known as ‘The Magnetes’ and the region they inhabited called ‘Magnesia’. The association is likely due to the discovery of magnetised ore in this region. There is also an old fable, which recounts how a shepherd known as Magnes happened to stumble upon a magnet. As the story goes, Magnes was wandering on a hilly area when he felt his feet clung to the earth. (The reason being his shoe nails getting stuck to the magnetite rocks that laid there) Much later, when the magnetic compass was invented, magnetism was finally put to practical use. 

In our modern world today, the uses of magnetism are boundless. Our everyday home appliances like television, refrigerators, speakers and microphones cannot function without their electro-magnetic properties. Even simple objects like doorbells, door latches and burglar alarms contain magnets as one of their vital components. The way in which magnets function was first discovered and scientifically explained in the 20th century. Hans Christian Oersted, a Danish physicist, was the first to demonstrate the correlation between electricity and magnetism. Based on a serious of experiments, humans finally got a basic understanding of a phenomenon that had puzzled us for centuries. 

In simple terms, magnetism is the physical property that makes certain elements attract or repel each other. The reason behind this invisible force is the presence of electric charges in particles, which forms the basis of both electricity and magnetism. To further understand how magnets interact with magnetic objects or other magnets, one must first learn about magnetic field and magnetic force. The field of influence around a magnet is called a magnetic field and magnetic force is the quantification of the magnetic attraction experienced. All moving charges create a magnetic field and all moving charges experience a magnetic force. Magnetic Induction is the process by which a conductor becomes magnetised when it is influenced by a magnetic field. The two types of Induction are Self-Inductance and Mutual Inductance. Self-Induction is when the Induction happens within the same coil and Mutual Induction is when one coil causes induction in the neighbouring coil. The process of electromagnetic Induction was first explained by Michael Faraday in 1831. His theories would later become incremental in the development of modern inventions like generators and transformers. 

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