In the context of heat transfer, what describes conduction?

Conduction is fundamentally defined as the process of heat transfer that occurs through direct contact between solid materials. When an object is heated, the particles within that object begin to vibrate and move more rapidly. This kinetic energy is then passed to neighboring particles through collisions, effectively transferring heat from one part of the material to another without the movement of the material itself.

Option B captures this process accurately by highlighting the transmission of heat via direct contact between solid objects. This is often experienced in everyday scenarios, such as touching a hot stove, where heat moves directly from the stove to your hand.

In contrast, the other options describe different modes of heat transfer. The movement of heated air represents convection, where warmth is transferred through the movement of fluids—either liquids or gases—stirred by temperature differences. The emission of energy through waves refers to radiation, which involves the transfer of heat through electromagnetic waves, allowing heat to travel through a vacuum (like sunlight reaching the Earth). The cooling of materials over time generally pertains to the transfer of heat away from an object, often involving various methods including conduction, but it does not specifically define conduction itself.