On Thu, Jun 23, 2011 at 3:10 AM, Mark Iverson <[email protected]> wrote:
> ** > Joshua wrote: > "The ratio of the partial pressure of the water vapor to the vapor > pressure of water is the relative humidity." > > The physics definition for RH is: > %RH = (Pw/Ps)*100 > Where Pw is the partial pressure of the water vapor and Ps is the > saturation pressure of water vapor... > > What's the 'vapor pressure of water'... sound like you're making this shit > up. > Nope. *"Vapor pressure* or *equilibrium vapor pressure* is the pressure<http://en.wikipedia.org/wiki/Pressure> of a vapor <http://en.wikipedia.org/wiki/Vapor> in thermodynamic equilibrium<http://en.wikipedia.org/wiki/Thermodynamic_equilibrium> with its condensed phases <http://en.wikipedia.org/wiki/Phase_(matter)> in a closed system. " "Meteorologists also use the term *saturation vapor pressure* to refer to the equilibrium vapor pressure of water or brine<http://en.wikipedia.org/wiki/Brine> above a flat surface, to distinguish it from equilibrium vapor pressure which takes into account the shape and size of water droplets and particulates in the atmosphere." They're pretty close in meaning, and the difference is too subtle to matter here.
