Heat Transfer Through Fluid Movement: Convection

Heat can be transferred in three primary ways: conduction, convection, and radiation.

• Conduction: This is heat transfer through direct physical contact, primarily in solids. Energy is passed from particle to particle without the particles themselves moving long distances.
• Convection: This method involves heat transfer through the movement of fluids (liquids or gases). When a part of a fluid is heated, it becomes less dense and rises, while cooler, denser fluid sinks, creating a cycle that distributes heat. This directly matches the question's description.
• Radiation: This is heat transfer through electromagnetic waves, like infrared radiation from the sun or a fire. It does not require a medium.
• Reflection: This is the bouncing back of waves or particles off a surface. It's related to how objects interact with radiation but isn't a method of heat transfer itself.

Therefore, the concept that explains heat transfer specifically through the movement of fluids (liquids or gases) is convection.