What’s a Watt? provides students with an engaging and hands-on approach to the exploration of concepts surrounding measuring energy, forms of energy, energy transfers and transformations, conservation of energy and energy efficiency. They develop an understanding of key energy concepts and measurements through a range of practical activities.
In the Power Hungry Appliances session students measure the amount of electrical energy transformed by a variety of household appliances. Students begin by pedalling the Earth Ed Energy Bike in order to understand how much power is being used when we turn on appliances. The students identify the energy transfers and transformations occuring as their peers pedal the bike to power up various appliances. Students learn about the chemical energy in food and many students are surprised to discover the length of time they would need to pedal the bike to transform the chemical energy (kilojoules) from a hamburger. After testing a variety of household appliances with a power meter, students learn how to calculate kilowatt hours and the financial and environmental cost of running these appliances. Students are often amazed when they compare their initial predictions with their results, discovering that an electric kettle requires up to 10 times more energy to operate than a small LCD TV.
The Incredible Energy Machines session begins with students having a fun discussion about the different energy transfers and transformations occurring in a music video featuring a Rube Goldberg style energy machine. The students then work in small groups to create their own Incredible Energy Machines using a wide variety of objects. The aim is to incorporate as many different energy transfers and transformations in a working machine as possible. Students think of some very creative ways to use heat energy, sound energy, light energy, kinetic energy and chemical energy.
Key Learning Outcomes:
- Identify with the concept of energy and challenge their preconceptions about what energy is.
- Understand that energy is conserved and can transform from one form to another.
- Demonstrate and describe energy transformations.
- Understand energy efficiency and measure and calculate the efficiency of energy transformations.
- Understand the relative power and energy usage of a range of domestic appliances.
Learning Standards (Australian Curriculum):
What’s a Watt? demonstrates the learning addressed through Year 8 of the Australian curriculum standards. In particular, it addresses:
- Energy appears in different forms including movement (kinetic energy), heat and potential energy, and causes change within systems
Science as a human endeavour
- Scientific knowledge changes as new evidence becomes available, and some scientific discoveries have significantly changed people’s understanding of the world
Science inquiry skills
- Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge
- Construct and use a range of representations, including graphs, keys and models to represent and analyse patterns or relationships, including using digital technologies as appropriate
- Communicate ideas, findings and solutions to problems using scientific language and representations using digital technologies as appropriate