... the process of "radiation". He would feel it even if there were no air between the fire and him.
A firefighter arrived at a burning building and felt the heat immediately this is due to the thermal energy transfered by the atmospheric air.
The firefighter felt the heat due to thermal energy transferred primarily by radiation, which involves the emission of infrared waves. This process allows heat to be sensed even without direct contact, as seen when standing in sunlight or near a hot oven. The human skin is particularly sensitive to infrared radiation, enabling the detection of heat sources efficiently.
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