ABSTRACT

People have always had an idea of energy. Anyone collecting or chopping firewood has a concept of energy. Anyone pulling a plough has a concept of mechanical work. In the UK, teachers from the Institute of Physics have taken the idea and proposed a better way of teaching energy. Kinetic energy, the potential energies, heat, chemical and nuclear energies are all described as energy stores, whereas electricity, sound and light are more helpfully described as energy pathways. The genius of energy is that it can incorporate unexpected phenomena – heat does not look like kinetic energy or potential energy, but James Joule found a way to incorporate it. Heat energy was a different matter. Heat already had an explanation. For most of scientific history, philosophers thought that heat was a type of substance. Another word which causes difficulty is work. Work sounds difficult: most learners would say that writing a page is more work than playing football for 10 minutes.