Re: IS this real science or a special effect?

Mike Van Pelt skreiv:

> The "Mad Scientist Guy" that Jay Leno has on every now and then did
> the "breathing sulfur hexafluoride" trick once.  After he did it, he
> hung upside down and breathed deeply for a few seconds to get it out
> of his lungs; he said that otherwise, much of it would stay there.
> 
> (I'm not sure how much I believe that; even though it's a very heavy
> molecule, there's still some mixing.)

There is more than "some" mixing, the lungs are infact very good at 
thouroughly mixing gases with different densities. At the speed and 
turbulence-level present in the lungs, the gases will be near perfectly 
mixed, even with -normal- breathing. (nevermind vigorous breathing)

I doubt you could find -any- detectable difference in sulfur 
hexafluoride-concentration in the lungs after taking 10 normal breaths 
standing up versus taking 10 normal breaths while hanging upside down.

The "must stand on your head" thing is a urban myth.


	Eivind Kjorstad