Transfer of Thermal Energy

2026 Syllabus Objectives

By the end of this topic, you should be able to:

Conduction:

• Describe experiments to demonstrate the properties of good thermal conductors and bad thermal conductors (thermal insulators)
• Describe thermal conduction in solids in terms of atomic/molecular vibrations and free electron movement in metals
• Explain why thermal conduction is poor in gases and most liquids
• Know that some solids conduct heat better than insulators but worse than good conductors

Convection:

• Know that convection is an important method of thermal energy transfer in liquids and gases
• Explain convection in terms of density changes
• Describe experiments to demonstrate convection

Radiation:

• Know that thermal radiation is infrared radiation and all objects emit it
• Know that thermal radiation does not require a medium
• Describe the effect of surface colour and texture on emission, absorption and reflection of infrared radiation
• Understand the conditions for an object to maintain constant temperature
• Know what happens when energy input and output rates differ
• Know how Earth's temperature is affected by radiation balance
• Describe experiments to compare good and bad emitters and absorbers of infrared radiation
• Describe how emission rate depends on surface temperature and surface area

Consequences:

• Explain everyday applications of conduction, convection and radiation (heating pans, room heating)
• Explain complex applications where multiple types of transfer occur (burning fire, car radiator)

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