If I purse my lips and blow air on my hand it's cold, but if I blow air with my mouth open, it's warm.  WHY
462469
The air inside your mouth is at body temp. close to 100 degress.  When you blow it out with your mouth wide open it comes out at that temperature.  But when you close your mouth down small, the air is compressed and then expands as it passes throug.  A gas that rapidly expands always cools (air conditioners and fridges use this principle).  There is a constant relationship between pressure, volume and temperature:  PV=nrT.
973898
That is a fantastic question.\nIt is a matter of humidity. The cold weather\nthat allows snow means the air is not humid\nenough to allow an electric current to travel\n(along the water vapor in the air) over the differently\ncharged clouds and sky. People who say temp are\nsort of right, but it is the low temp that leads to the low\nhumidity that causes the "problem".\n\nThanks for asking such a good question.
15388
Freeze by and far.  You body just shuts down (goes into shock) and everything stops.  There's a big difference between having your hands or feet be so cold you can't feel them to getting a burn on your hand or foot.  I imagine the difference is the same with freezing to death vs burning.
524560
Yup, it's A.  The air is saturated with water, so the sweat on your body doesn't have the chance to evaporate to cool you.
1107382
it doesn't normally get a lot of blood (unless it's hard).  same reason your hands/feet get cold.
1163893
It is because the continuous flow of air can dehydrate an erode the mucosa. so the body has a mechanism to rehydrate the mucosa so it wont be damaged by the air flow\nthe way in which the body does this is by opening the blood flow through one nostril causing a normal swelling of the mucosa, this swelling prevents air from passing through there and at the same time provides water to the cells. then the same thing  happens on the other side.\nThe open side has a little less blood flow than the closed side. \nthey switch almost every 20 to 30 minutes \nbesides this the blood flow is designed to warm the air and humidify it although most of this humidification will take place in the trachea (windpipe) where there is water in vapor form.
1007111
Water distributes heat much faster than air can, thus, if your are warmer, it will absorb your body heat.
1163332
if u mean blow,,,\nwind blows because of the pressure difference between 2 places... it blows from a place of high pressure to that of low pressure....\nand i think this pressure difference may arise sometimes due to a temperature difference also
144302
Hot air is lighter than cold air.\nWhen the ground is heated up by the sun, the air above it heats up too.\nThe warmer air near the ground gets pressed down on by the cold air above it.  When this happens, the air is essentially 'squeezed' out as the colder air moves into the area.\nAny time there is a difference between temperature of different layers of air, there is often movement between those layers to create a blance between them.  They cannot just switch places because one blocks the other, so they tend to move out of each other's way.\nIf you have enough of a difference in temperatures, you can end up with differences in pressure over an entire area.  When these pressure zones collide, they can result in heavy winds or even large storms.
950514
MY HANDS ARE LIKE THAT TOO. WHEN I USE THE COMPUTER THEY REALLY GET COLD OR WHEN I READ A BOOK. AS LONG AS I KEEP MOVING THEM THEY'RE OK. JUST PART OF GROWING UP.
1136431
Should be simple.  Warm air rises because it is less dense than cool air.  Cool air rushes in to replace the rising warm air.\n\nPlug this simple formula into the complex real world of spinning globe, equitorial heat and polar regions & you get weather.
906611
breathe into your hands. your breath warms your hands and in turn you begin breathing warm air. breathing warm air triggers the bodies machinary to beginning heating up  the body parts. of course this is only a quick fix and trick. you need to get to cover or clothing immeadiately.
5905
As I undertand it, the difference is not in temperature but in wind chill. A hot breath is slow with little force in it, like a hot breeze on a hot day. A cold breath is much faster like how it feels cooler when the wind blows.
1107261
It seems you are confusing the term 'blowing wind' with the idea of breathing. The wind is not 'blown out' from anywhere when it warms, so there is no question of it being sucked back in when cooled.\n\nWind is just the movement of air from areas of higher pressure to areas of lower pressure. When some part of the Earth warms up, it heats the air above it. Warm air expands and rises. It has lower pressure. Cooler air from nearby places has higher pressure, so it comes in to the low pressure area.\n\nSo wind is actually caused by the differences of temperature and pressure in areas near each other. There is no blowing out or sucking in. Its simply a movement of air from one place to another.
587432
Colder air is "thicker," moves much more slowly than does hot air, and is heavier than warmer air...Air will set up a gradient from the coldest at the bottom to the hottest at the top in a container...
196746
It's better to breathe through your mouth.  Your mouth is bigger allowing you to get more oxygen.
1085969
Because it causes the moisture on your hand to flash freeze and stick to it.  Just don't do it with your tongue!