AFOQT Practice Test

Which process involves hot air rising and cold air sinking?

1. Conduction

2. Radiation

3. Convection

4. Evaporation

The correct answer is: Convection

The correct answer is convection. This process involves the movement of heat through fluids, such as air or water, due to the differences in temperature and density. When air is heated, it becomes less dense and rises. Conversely, cooler air is denser and sinks. This creates a continuous circulation pattern as warm air rises, cools, and then sinks, allowing for efficient heat transfer. Conduction involves the direct transfer of heat through a material without the movement of the material itself, while radiation is the transfer of heat through electromagnetic waves. Evaporation refers to the change of a liquid into vapor and does not directly involve the movement of air layers. Thus, convection best describes the process in which hot air rises and cold air sinks.