If you are near something hot, say an open flame, you can feel the heat radiating from the fire. I have a juvenile understanding of thermodynamics, but I understand that there is energy radiating from the heat source which is what I’m feeling.
By contrast, if you hover your hand near an ice cold drink, you can FEEL the cold before even touching the glass.
How is this possible since my hand is seemingly radiating more energy than the drink is? Is what I’m feeling just the energy leaving my hand and entering the drink?
In: 9
You’re just feeling the convective action of the cold air against your skin. When you sense the radiant heat of a fire, the temperature difference is significant, around 1000 °F.
When the temperature of everything around you is pretty close to the temperature of your skin, you don’t lose or gain a lot of heat through radiant heat, because you radiate about as much as you absorb. The ice is only a few tens of degrees colder than you are, so you wouldn’t notice.
It does cool off the air around it, so if you get close, your skin will heat up that air, and convection will cause it to circulate as it warms up, being replaced with more cold air, and carrying away enough heat that you can feel it.
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