What process describes the direct transmission of heat between solid materials?

Conduction is the process that describes the direct transmission of heat between solid materials. This occurs when there is a temperature difference between two objects that are in physical contact with each other. In this physical contact, heat energy from the hotter object is transferred to the cooler one through particle-to-particle interactions. These particles vibrate more in the hotter material and pass on their energy to adjacent, slower-moving particles in the cooler material.

This transfer continues until thermal equilibrium is reached, meaning the temperatures of the two materials equalize. This process is fundamental in many applications, including cooking, heating systems, and the heating of fireplaces, where the transfer of heat from flames to surrounding solid materials occurs through conduction.

The other options describe different modes of heat transfer: convection involves the movement of fluids (liquids and gases), radiation is the transfer of heat through electromagnetic waves, and absorption refers to the process of a material taking in energy, which doesn’t necessarily relate specifically to the direct transmission of heat between solid materials.