1. Liverpool Physics Teachers Conference 2004
25 July 2019
Liverpool Physics Teachers Conference 2004

2. Teaching energy Gary Williams
Work in progress
Teaching energy
Gary Williams
This talk is based on a paper that Tony Reeves and I wrote about work that we’d done at Christ College, Brecon.
25 July 2019
Liverpool Physics Teachers Conference 2004

3. Liverpool Physics Teachers Conference 2004
Historically
UK physics teaching has become more conceptual
Nuffield introduced the ideas of different labels – sound energy, food energy etc
This idea has been taken too far
We have reinforced the idea of caloric rather than destroying it.
25 July 2019
Liverpool Physics Teachers Conference 2004

4. Liverpool Physics Teachers Conference 2004
The problem
Energy doesn’t exist, it’s a mathematical “quantity”
The concept of energy is a powerful tool for showing equivalence between systems
There’s a lot of new language on the way to understanding
It’s in exams
25 July 2019
Liverpool Physics Teachers Conference 2004

5. Liverpool Physics Teachers Conference 2004
A solution
Should start where we are now
Should finish where we want to be
Must tackle the language problem
Must highlight the underlying mathematical nature of energy
Needs to address likely exam questions
25 July 2019
Liverpool Physics Teachers Conference 2004

6. Boohan and Ogborn – Energy and change
25 July 2019
Liverpool Physics Teachers Conference 2004

7. The CCB Energy approach
Nuclear
Gravitational potential
Internal
Elastic potential
Chemical
Kinetic
Heating
Sound
Radiation
Electrical work
The idea was based on the Boohan-Ogborn energy diagrams in the ASE project “energy and change”
25 July 2019
Liverpool Physics Teachers Conference 2004

8. The big picture – a system
Transformer
Energy sink
Energy source
25 July 2019
Liverpool Physics Teachers Conference 2004

9. A power station – a source
Chemical
Electrical work
25 July 2019
Liverpool Physics Teachers Conference 2004

10. A light bulb – a transformer
Lamp
25 July 2019
Liverpool Physics Teachers Conference 2004

11. Lifting a weight – a sink
25 July 2019
Liverpool Physics Teachers Conference 2004

12. Liverpool Physics Teachers Conference 2004
A try this example
The stereo runs off mains electricity
The device converts the energy
The energy goes where?
Into the environment.
25 July 2019
Liverpool Physics Teachers Conference 2004

13. Liverpool Physics Teachers Conference 2004
Mains electricity comes from power stations
25 July 2019
Liverpool Physics Teachers Conference 2004

14. Liverpool Physics Teachers Conference 2004
Stereo
The stereo is just like a loudspeaker
25 July 2019
Liverpool Physics Teachers Conference 2004

15. Liverpool Physics Teachers Conference 2004
The sound goes into the environment
25 July 2019
Liverpool Physics Teachers Conference 2004

16. Liverpool Physics Teachers Conference 2004
Stereo
25 July 2019
Liverpool Physics Teachers Conference 2004

17. Liverpool Physics Teachers Conference 2004
Stereo
Write the word descriptions under the symbols
25 July 2019
Liverpool Physics Teachers Conference 2004

18. Liverpool Physics Teachers Conference 2004
We had:
Lamp
So where’s the heating?
25 July 2019
Liverpool Physics Teachers Conference 2004

19. A normal light bulb is only about 10% EFFICIENT.
25 July 2019
Liverpool Physics Teachers Conference 2004

20. Liverpool Physics Teachers Conference 2004
Lets draw it like this:
Lamp
90%
10%
Then we know what’s going where.
25 July 2019
Liverpool Physics Teachers Conference 2004

21. Liverpool Physics Teachers Conference 2004
Motor
65%
30% 5%
25 July 2019
Liverpool Physics Teachers Conference 2004

22. So a power station would look like:
Boiler
Turbine
Generator
30%
70%
50%
15%
20%
15%
10% 5% 5%
25 July 2019
Liverpool Physics Teachers Conference 2004

23. Liverpool Physics Teachers Conference 2004
25 July 2019
Liverpool Physics Teachers Conference 2004

24. Most power stations are very similar:
Turbine
A turbine changes kinetic energy so that it’s more useful
25 July 2019
Liverpool Physics Teachers Conference 2004

25. A generator converts kinetic energy into electrical work
Then the electricity gets sent to your home.
25 July 2019
Liverpool Physics Teachers Conference 2004

26. Liverpool Physics Teachers Conference 2004
Hydroelectricity
Turbine
Generator
Falling water turns a turbine which drives a generator
25 July 2019
Liverpool Physics Teachers Conference 2004

27. Liverpool Physics Teachers Conference 2004
The Elan Valley scheme in the Cambrian Mountains of mid-Wales comprises five reservoirs and four dams, built between the end of the 19th century and The reservoirs hold 199 million tonnes of water and are the main water supply source for Birmingham.
During the 1990s, the existing water supply was harnessed to generate electricity. The scheme generates power to meet the needs of nearly 11,000 homes, avoiding carbon dioxide (CO2) emissions of 26,200 tonnes a year.
25 July 2019
Liverpool Physics Teachers Conference 2004

28. Liverpool Physics Teachers Conference 2004
25 July 2019
Liverpool Physics Teachers Conference 2004

29. Liverpool Physics Teachers Conference 2004
10. Which boxes best show the useful energy transfer which takes place in an electric bell? A B
Electric Bell
Radiation
Sound
Electric Bell
Electrical work
Kinetic D C
Electric Bell
Electric Bell
Electrical work
Sound
Heating
Radiation
25 July 2019
Liverpool Physics Teachers Conference 2004

30. Liverpool Physics Teachers Conference 2004
Why does it work?
It’s very visual
Pupils don’t need to know the language straight away
It’s very interactive
25 July 2019
Liverpool Physics Teachers Conference 2004

31. Liverpool Physics Teachers Conference 2004
Why did we do it?
The teaching of energy needs some common ground
Our teaching of this subject needs to improve
Too often pupils in the past have little long term recall of this topic
25 July 2019
Liverpool Physics Teachers Conference 2004

32. Liverpool Physics Teachers Conference 2004
Where should we go?
Banish all forms of energy that don’t have equations at GCSE?
Reduce the forms of energy to 4 – the same as the number of fundamental forces? (or 3?)
25 July 2019
Liverpool Physics Teachers Conference 2004

33. All the resources can be downloaded from the Christ College website:
From the menu follow: Academic>>>subject list>>>>Physics
25 July 2019
Liverpool Physics Teachers Conference 2004