(b) Energy transfers

Describe energy transfers involving energy stores:

• energy stores: chemical, kinetic, gravitational, elastic, thermal, magnetic, electrostatic, nuclear
• energy transfers: mechanically, electrically, by heating, by radiation (light and sound)

Use the principle of conservation of energy

Know and use efficiency = useful energy output ÷ total energy output × 100%.

Describe a variety of everyday and scientific devices and situations, explaining the transfer of the input energy in terms of the above relationship, including their representation by Sankey diagrams

Describe how thermal energy transfer may take place by conduction, convection and radiation

Explain the role of convection in everyday phenomena

Explain how emission and absorption of radiation are related to surface and temperature

Practical: investigate thermal energy transfer by conduction, convection and radiation

Explain ways of reducing unwanted energy transfer, such as insulation