Powerful Ideas for Powerful SolutionsHeat is transferred via three different mechanisms:
Radiation—Radiation is the transfer of heat via electromagnetic waves with wavelengths in the infrared region of the spectrum. These waves excite the atoms in materials through which they pass causing an increase in the atoms' energy thereby raising the temperature of the materials. Feeling the warmth of the sun on a still day or the heat emanating from a fireplace are examples of radiative heat transfer.
Conduction—Conduction is the transfer of heat by physical contact between source and sink. Electric stoves transfer heat by conduction. The pan sits directly on the hot burner and heat is transferred from the burner to the pan through this contact.
Convection—Convection involves the movement of warm liquid or gas between the heat source and the heat sink. The most common convection mediums are water and air. Most modern space-heating systems transfer heat by convection. The heat source, such as a furnace, draws in air, heats it, then distributes this warm air to the spaces in the structure.
