If heat is the measure of atomic kinetic energy and cold is technically the lack of heat then how can we feel radiated cold? Like if you put your hand near some ice you can feel the cold? How can the lack of something radiate?
In: Physics
So hold your hand out, it feels neither cold or hot. This is because your hand loses energy due to black body radiation, however, the wall on the other side of the room is also warm, so it also loses energy due to black body radiation. That energy leaving your hand goes into the wall, and the energy leaving the wall goes into your hand. Since these are roughly the same temp, you skin maintains a constant temp since it absorbs the same amount of heat as it emits.
If instead of a wall it was a fire, your skin would warm because the fire emits much more energy than your hand emits, so your skin warms up and you feel that.
If instead of a wall it was a giant block of ice, well then your hand would emit energy, but none would come off the block of ice. This causes your skin to cool, and you can feel that.
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