The sun sending out electromagnetic waves is best describes the source of radiation heat.
Radiation heat is the form of electromagnetic waves.
Radiation heat, commonly referred to as thermal radiation, is the electromagnetic radiation that defines how photons exchange heat. The technique of heat transfer known as radiant heat does not require a medium to be propagated in.
Two molecules colliding with each other produce kinetic energy, moving objects have kinetic energy. Radiation heat is thermal energy. Sun directly sends thermal radiation through electromagnetic waves.
Hence , The sun sends out electromagnetic waves directly is best describes the source of radiation heat.
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