0.1 Introduction to 'what is energy' and the law of conservation of energy

The concept of energy emerged in the 19th century - The idea was used to explain the work output of steam engines and then generalised to understand other heat engines.

We now know energy can exist in many forms and this became a key tool for understanding chemical reactions and biological systems and not just the physics of technology and engineering.

Energy can be very simply defined something that something the ability to do work i.e. energy can make things happen - induce any sort of change in a system..

The Law of conservation of energy states that energy cannot be created but only changes from one form to another. In other words you can't use up energy, you can only change it from one form to another.

e.g. (i) braking a car involves kinetic energy converted to thermal energy from friction of the brakes and often sound energy too,

or (ii) using a battery powered torch with a metal filament bulb converts chemical potential energy into electrical energy which is then converted into heat and light.

You can also consider applying to transferring energy from one energy store to another.

You need to know what the different forms of energy stores, types of energy and examples of energy conversions and transfers between energy stores.

 In which different types of energy can exist?

 You should be able to give brief description of examples of the different  forms of energy and their interconversion. Lots more examples are described in Part 0.3