UNIT 3


History of electricity and careers in electricity In this unit you will learn about:


• the history of the discovery of electricity • notable events in the history of electricity in South Africa • careers to do with electricity.


History of the discovery of electricity


The first discoveries of electricity were made more than 2 000 years ago. The ancient Greeks discovered that when amber was rubbed against cloth, lightweight objects stuck to it. They discovered static electricity. Some of the most important discoveries about electricity are listed here.


Table 1 Important discoveries about electricity Year


1600 New words


electromagnetic induction – the magnetic effect of electric current that causes an electromagnet to form


national grid – the network of power lines that supplies electricity throughout a country


1752 1800 1820 1831


1878 1881


1890 1905


1926 Discovery


William Gilbert invented the term electricity (from the Greek word for amber elektra). He was the first person to describe the Earth’s magnetic field and to realise that there is a relationship between magnetism and electricity.


Franklin proved that lightning is a form of electricity. Alessandro created the first simple battery.


Hans Christian Oersted discovered magnetic fields caused by electricity.


Michael Faraday discovered that when a magnet is moved inside a coil of copper wire, a tiny electric current flows through the wire in electromagnet induction. This discovery later led to the invention of electric motors.


Joseph Swan demonstrated the first electric light bulb in Britain. A few months later, Thomas Edison made the same discovery in America.


The first public electricity supply was generated in England using a water- wheel at a nearby mill.


Turbine-driven generators were introduced to produce electricity.


Albert Einstein demonstrated that light energy could be used to produce elec- tricity and the idea behind photovoltaic cells was born.


The first national grid was introduced in England.


1930–40s Hydro-electric power stations were built in Scotland and Wales, but the ma- jority of electricity generation was from burning coal.


1930–40s Electrical household appliances were introduced – mains-powered radios, vacuum cleaners, irons and fridges.


1956 2000


The first large-scale nuclear power station opened at Calder Hall in Cumbria in England.


The world’s first commercial wave power station on the Scottish island of Islay began to generate electricity.


126 Topic 3 Series and parallel circuits


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38