Why does the way your mouth is open have an effect on the temperature of the breath you blow out?

I think it has to do with the speed of the air coming out of your mouth. Air from your lungs would be warmed to body temperature no matter what, but when it’s blown fast (through a tiny peephole), it feels cool to your skin because of evaporative cooling. When you open your mouth wide, the air comes out slowly, so you just feel the effect of the body-temperature warmth.

As any mass, including, air increases velocity (restricted opening), and losses pressure (higher pressure inside the body, lower outside), it losses heat.

This is the same way an air conditioner works.

^^ both are right. The :^o breath, while still warm, seems cooler because it comes out faster and doesn’t have the chance to be warmed like the slow :^O breath does.

the emoticons in this thread are hilarious

I remember my physics teacher explained this on the first day of his class junior year. I had completely forgotten until today. :)

while the :^u mouth kiss is pleasurable, the :^U mouth kiss is much more enjoyable due to the increased amounts of heat and love juice

It’s because when you create a high-velocity airstream with your pursed lips, that jet of air entrains (draws in) lots of the cooler surrounding air, so that much of what ends up hitting your hand is room air, not breath. If you put your finger right up against the air stream as it leaves your lips, it will feel warm because it hasn’t yet entrained the cooler air (note that this shows that the cooling isn’t related to velocity, since the air is at its highest velocity right at the lips).

The lower velocity puff from your open mouth doesn’t entrain surrounding air like the jet does, so you’re feeling mostly the warm breath.

Thanks guys. :D
Also; @Grisaille, part of why I wanted to ask this so bad was to have a serious question and use them :p