Thinking about this while I sit in 20 degrees heat sweating my ass off. Like shouldn’t anything under 37 degrees feel cold to us?
In: 34
Your internals run at that temperature, not your skin. Your body is always in a balancing state of producing heat internally and bleeding it off to the environment. You bleed off your internal heat energy over time as it dissipates out to your skin. Hot and Cold are actually a measure of whether your skin bleeds that heat off faster than it dissipates out of your body. This is about whether what your contacting with your skin conducts more heat away from the body faster than your body replenishes it.
So your sitting inside and its 20 degrees Celsius. Touch something metal that’s obviously 20 degrees Celsius(sitting inside just like you). It feels cold because metal conducts heat VERY well and so you shed heat energy from your skin(some temperature above room temperature) to that metal object(room temperature) much faster than heat is dissipating out to your fingers. The same is true with water, it will absorb heat from you so fast it will feel cold and even 15 degree Celsuis water can kill you by lowering your body temperature too fast. Water is particularly dangerous because as a liquid it envelopes you and touches every square inch of your skin.
Conversely the air around you is a poor conductor of heat energy, air pockets are actually great insulators. Consider regular fiberglass insulation, the pink stuff you see in home insulation applications. It’s the fiberglass doesn’t do much for insulation, its the billions of little air pockets it makes. This is actually why we have body hair, it minimizes air’s natural movement over our skin and allows you to retain body heat(feel warm) in cold air because the heat lose from skin to air is really really small, especially when the air doesn’t move around. Your body heats up the air immediately surrounding your skin, but if that air doesn’t really move away and get refreshed, you stop shedding heat pretty quick, even though the outside air could be quite a bit colder.
This is why you can feel warm in the sun even when its cold out, but as soon as the wind picks up and blows the air around your body it feels cold again. It’s why a fan can make you feel cool even though its just circulating air that’s all the same temperature. It’s also what “wind chill” is, which is a silly way of trying to quantify how much colder the air will feel, even though its still just the same temperature.
Latest Answers