Gasp!
This list is amazing. Early in the week, I posted a note on the
observation that bearings don't dry up in an idle engine, Denise made an
innocent reply that included a comment about batteries sitting on concrete
and now we're into cloud physics and electrical circuit theory.!!
In hopes of putting the issue to bed so we can get back to important things
like whether the near-side becomes the off-side in the Southern hemisphere
(or whatever that thread was about), shown below is the relationship
between atmospheric density and moisture content: (it must be right - I
just looked it up)
D=1.2929(273.13/T)(B-0.3783e)/760 B= barometric pressure
T= absolute pressure
e= vapor press. of the moisture
It didn't mean anything to me either so I plugged in some typical values:
At constant pressure (760mm) and temperature (20C) the density (in g/l) is
1.290 at a dew point of 0C (fairly dry air), 1.287 at a dew point of 10C
(damper) and 1.282 at a dew point of 20C (damp).
So atmospheric density goes DOWN with increasing water vapor, all else
being constant.
Now, what was the question? Oh yes, "why do batteries discharge when
stroed on concrete?" I have no idea.
(And all this discussion has missed the REAL question: what holds clouds
up? They're not vapor but rather condensed drops of water; seems like they
should always rain down....)
Russ Wilson
J. Michael Roach wrote:
>As I remember it, humid air is MORE dense than dry air. However,
>barometric pressure decreases as a result of the amount of air, not
>the humidity of the air. High pressure areas (such as a storm) move
>toward the low pressure area. That's why low pressures mean an
>eminent storm.
>
>Now that I've confused the issue, is there someone out there who can
>tell us which is correct?
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