Shouldn't any air temp. below 98.6 °F feel cool?

[boxerfangg]

I was taught that heat always goes from high to low. Now shouldn't any air temp. below 98.6 °F feel cool because the air would be taking heat away from your body?

[Bignose]

Clothes trap a fair amount of heat near your body as does body hair. Also, radiation from the sun will warm you. Also, your muscles release heat as they are worked.

 

Moral of the story is I think you need to perform the experiment where you strip naked, shave everything, and sit still in the shade on the next 98 degree day and see how it goes...

Edited June 29, 2011 by Bignose

[Cap'n Refsmmat]

I'd expect that since your body constantly produces additional waste heat, you'd need the air to be several degrees cooler so that the waste heat can be adequately dumped into the environment. If you sat in 98.6 degree air, the heat your body produces would have nowhere to go.

[Marqq]

98.6°F is your body's internal temperature. Your body produces heat constantly, at around a maximum of 98.6°F. As you near your external surface, and especially the extremities, the average temperature drops to around 91°F₁. That's why they have to stick the thermometer up in your [acr=armpit or under your tongue..what did you think I was gonna say?]...[/acr], because the heat doesn't escape so quickly from there. Certain organs even have different temperature requirements to function well, though the difference is very slight.

Your skin, though, is supposed to regulate the transfer of thermal energy to and from your environment. Feeling hot or cold is less a reaction to your internal temperature, and more a reaction to your skin temperature. Since your body is always producing heat, an external temperature equal to your internal temperature allows much less of that excess energy to be expelled. In such a situation, your poor body can barely keep up!

 

1:http://{http://hypertextbook.com/facts/2001/AbantyFarzana.shtml}

 

 

 

[swansont]

I'd expect that since your body constantly produces additional waste heat, you'd need the air to be several degrees cooler so that the waste heat can be adequately dumped into the environment. If you sat in 98.6 degree air, the heat your body produces would have nowhere to go.

Precisely, along with Marqq's observation that skin temperature is lower. This is why you sweat when it's warmer — evaporation removes about 580 cal/gram. The ambient temperature that allow you to be in steady-state and shed the ~100W of power from your metabolism is in the low/mid 70s (ºF), which is why you are comfortable a few degrees cooler while clothed.

[Brainteaserfan]

So does wind make you feel cooler because it removes the heat that your body has just expelled?

[swansont]

So does wind make you feel cooler because it removes the heat that your body has just expelled?

Wind aids in evaporation and convection; evaporation is probably more important.

[alpha2cen]

Temperature, relative humidity and speed of the wind are important factors. Low temperature removes heat more fast, and low relative humidity makes the water easily evaporate. And, the fast evaporated water drops surround temperature more lower. This is a heat and mass transfer problem. High wind speed reduces the heat and mass transfer resistance.

[rktpro]

@alpha2cen,

Just to add surface area as a factor.