Energy and Electricity 22/09/2018 Energy and Electricity W Richards The Weald School

Gravitational potential The 9 types of energy 22/09/2018 Type 3 example sources Type 3 example sources Heat Kinetic (movement) Nuclear Sound Light Chemical Electrical Gravitational potential Elastic potential

Electricity Light + heat Energy changes 22/09/2018 To describe an energy change for a light bulb we need to do 3 steps: 1) Write down the starting energy: 3) Write down what energy types are given out: 2) Draw an arrow Electricity Light + heat What are the energy changes for the following…? An electric fire A rock about to drop An arrow about to be fired

Words – electrical (x2), light, chemical Electrical Energy 22/09/2018 Consider a simple circuit: The job of the battery is to convert ______ energy into _________ energy… The job of the bulb is to convert the _________ energy it receives from the battery into ______ energy. Words – electrical (x2), light, chemical

Electrical Energy 22/09/2018 Hi. I’m Ernie Electron and I’m going to show you how I get energy around a circuit. Energy

Electrical Energy 22/09/2018 Hi. I’m Ernie Electron and I’m going to show you how I get energy around a circuit. Energy

Electrical Energy 22/09/2018 Hi. I’m Ernie Electron and I’m going to show you how I get energy around a circuit. Energy

Fuels 22/09/2018 A “fuel” is something that can be burned to release heat and light energy. The main examples are: Coal, oil and gas are called “fossil fuels”. In other words, they were made from fossils.

22/09/2018 Wind Power

22/09/2018 Tidal Power

22/09/2018 Wave Power

22/09/2018 Hydroelectric Power

22/09/2018 Geothermal Energy

22/09/2018 Solar Power

22/09/2018 Power stations

What does each part do? 22/09/2018 The boiler is where the fuel is burnt to boil water The steam from the boiler is used to turn a turbine The turbine is connected to the generator, which acts like a dynamo – it generates electricity out of movement The steam is cooled down and turned back into water in the cooling tower

Energy Transfer diagrams 22/09/2018 Consider a light bulb. Let’s say that the bulb runs on 100 watts (100 joules per second) and transfers 20 joules per second into light and the rest into heat. Draw this as a diagram: “Input” energy “Output” energy 20 J/s light energy 100 J/s electrical energy 80 J/s heat energy (given to the surroundings)

Example questions Consider a computer: Consider a kettle: 22/09/2018 Consider a computer: 150 J/s electrical energy 10 J/s wasted sound 20 J/s wasted heat Useful light and sound How much energy is converted into useful energy? What is the computer’s efficiency? Consider a kettle: Work out each energy value. What is the kettle’s efficiency? Sound energy Wasted heat Heat to water 2000 J/s electrical energy