Air is heated by a heater placed on the floor of a room.
The density of the air changes as its temperature increases. This causes thermal energy to be transferred throughout the room.
How does the density of the heated air change, and what is this energy transfer process?
Decreases; conduction
Decreases; convection
Increases; conduction
Increases; convection
301 exam-style questions on CIE IGCSE Physics 2.3 Transfer of thermal energy, covering 2.3.1a Thermal conductors and thermal insulators, 2.3.1b Explaining thermal conduction, 2.3.2 Convection, 2.3.3a Thermal radiation, 2.3.3b Surface colour and texture, 2.3.3c Rate of emission and absorption of radiation, and 2.3.4 Consequences of thermal energy transfer. Each one has a worked solution and a mark scheme showing where the marks go.