2.3.1 Conduction

CORE OBJECTIVES:

• Describe experiments to demonstrate the properties of good thermal conductors and bad thermal conductors (thermal insulators)

EXTENDED/SUPPLEMENT OBJECTIVES:

• Describe thermal conduction in all solids in terms of atomic or molecular lattice vibrations and also in terms of the movement of free (delocalised) electrons in metallic conductors
• Describe, in terms of particles, why thermal conduction is bad in gases and most liquids
•  Know that there are many solids that conduct thermal energy better than thermal insulators but do so less well than good thermal conductors

2.3.2 Convection 

CORE OBJECTIVES:

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

EXTENDED/SUPPLEMENT OBJECTIVES:-NONE

2.3.3 Radiation

CORE OBJECTIVES:

• Know that thermal radiation is infrared radiation and that all objects emit this radiation
• Know that thermal energy transfer by thermal radiation does not require a medium
• Describe the effect of surface colour (black or white) and texture (dull or shiny) on the emission, absorption and reflection of infrared radiation

EXTENDED/SUPPLEMENT OBJECTIVES:

• Know that for an object to be at a constant temperature it needs to transfer energy away from the object at the same rate that it receives energy
•  Know what happens to an object if the rate at which it receives energy is less or more than the rate at which it transfers energy away from the object
•  Know how the temperature of the Earth is affected by factors controlling the balance between incoming radiation and radiation emitted from the Earth’s surface
• Describe experiments to distinguish between good and bad emitters of infrared radiation
•  Describe experiments to distinguish between good and bad absorbers of infrared radiation
•  Describe how the rate of emission of radiation depends on the surface temperature and surface area of an object

2.3.4 Consequences of thermal energy transfer

CORE OBJECTIVES:

• Explain some of the basic everyday applications and consequences of conduction, convection and radiation, including:
• (a) heating objects such as kitchen pans
• (b) heating a room by convection

EXTENDED/SUPPLEMENT OBJECTIVES:

• Explain some of the complex applications and consequences of conduction, convection and radiation where more than one type of thermal energy transfer is significant, including: (a) a fire burning wood or coal (b) a radiator in a car