On Fri, 12 Dec 2003 03:36:59 GMT, Rick wrote:

Steven Shelikoff wrote:

Why? Did you find somewhere that says an absolute zero/zero vacuum is
0.0049 psi?

I just made it up. Why don't you look it up and tell us, tell us
anything except -14.7 psi.

I did. I said you couldn't define it as -14.7 psig and that it was 0
psi. Do you have anything to suggest that absolute zero vacuum is not 0
psi?

This thread is turning into a "How many angels can dance ..." argument
where you guys can't even define and angel.

This stuff isn't rocket science. To expand on Rod's contribution, the
real metrics are available, the standards used throughout the world and
their definitions are readily available to those who prefer to speak the
language of science and technology rather than technical pig latin.

All you accomplish by saying -14 psi is to sound very very ignorant of
how pressure is measured and its standard conversions.

If by psi you mean psia, there is no such thing as -14 psia. If you
mean psig, all -14 psig means is that the pressure you're measuring is
14 psi less than the pressure surrounding it. That *could* be an
absolute vacuum *if* the pressure surrounding the gauge is 14 psia.

There are such things as vacuum gauges though, that read positive
numbers as the pressure they're reading decreases. Hell, I have 3 of
them on my boat. Of course, if the pressure they're reading is higher
than the surrounding pressure, they'll go negative until the needle hits
the stop that's just below 0.

All the stuff I've said above is actually pretty simple. What about it
don't you understand? Is it the fact that gauge pressure can be
negative? Is that what's throwing you for a loop?

Steve