How is heat transferred through liquids and gases?

Heat transfer through liquids and gases primarily occurs through convection. This process involves the movement of fluid – whether it's liquid or gas – caused by differences in temperature and density within the fluid. When a portion of the fluid is heated, it becomes less dense and rises, while cooler, denser fluid sinks. This creates a circulation pattern that effectively distributes heat throughout the fluid medium.

Convection can be categorized into two types: natural convection, which occurs due to buoyancy effects (such as warm air rising), and forced convection, which involves external forces like fans or pumps to enhance fluid movement. This mechanism is crucial in many applications, including heating and cooling systems, natural weather patterns, and even in the functioning of aircraft engines.

In contrast, conduction refers to heat transfer through direct contact between materials, which is less effective in liquids and gases due to their fluid nature. Diffusion describes the movement of particles from an area of higher concentration to one of lower concentration, but it does not specifically refer to heat transfer. Radiation involves the transfer of heat through electromagnetic waves and does not require a medium; hence it operates differently from the mechanisms at play in liquids and gases.