Heat transfer by electromagnetic waves is known as?

Heat transfer by electromagnetic waves is known as?

• A. Conduction
• B. Convection
• C. Evaporation
• D. Radiation

Answer: (D)

Radiation is the transfer of heat by electromagnetic waves. It can happen through empty space, so no medium is needed—think of the Sun warming the Earth or a fire warming your hands without touching them. This differs from conduction, which requires direct contact between substances for energy to pass from molecule to molecule, and from convection, which involves the bulk movement of a fluid carrying heat. Evaporation is a phase-change process that involves energy transfer but is not the mechanism described by electromagnetic waves. So the term for heat transfer by electromagnetic waves is radiation.

Radiation is the transfer of heat by electromagnetic waves. It can happen through empty space, so no medium is needed—think of the Sun warming the Earth or a fire warming your hands without touching them. This differs from conduction, which requires direct contact between substances for energy to pass from molecule to molecule, and from convection, which involves the bulk movement of a fluid carrying heat. Evaporation is a phase-change process that involves energy transfer but is not the mechanism described by electromagnetic waves. So the term for heat transfer by electromagnetic waves is radiation.