What type of heat transfer is conduction?

Conduction is defined as the transfer of heat through direct contact between materials. This occurs at the molecular level, where higher-energy (hotter) molecules transfer some of their kinetic energy to neighboring lower-energy (cooler) molecules when they come into contact. As a result, heat flows from the warmer substance to the cooler one until thermal equilibrium is reached.

This process is particularly significant in solids, where particles are closely packed, allowing for the efficient transfer of energy. For instance, when one end of a metal rod is heated, the energy moves along the rod through direct collisions between the atoms or molecules.

In contrast, other forms of heat transfer, such as convection and radiation, involve different mechanisms. Convection occurs in fluids, where heat is transferred by the movement of the fluid itself, and radiation involves the emission of energy in the form of electromagnetic waves, which can occur in a vacuum. Thus, understanding conduction as direct heat transfer makes it distinct from these other processes.