Jeff Wisnia wrote:
Terry wrote:

Where did you learn this? "of a square column of water 1 inch on each
side"

You make it sound like the density of water is dependent upon the
volume of
it's container.


Why did you come up with that critique? His explanation makes perfect
sense and is correct.

I often explain water pressures developed by gravity the same way.

Happy Holidays,

Jeff



When I read Andy's statement I had the same impression as
Terry. 10 inches of water has nothing to do with size of
the column. On the other hand, you have to know the weight
of a 1 inch square column to convert to PSI (pounds per
square inch), which is what Andy said he was doing.

Pressure measurements are confusing because so many
different measures are use. PSI is common to everyone,
inches of water are used for low pressures. Inches of
mercury are used for somewhat higher pressures. Atmospheres
is a convenient measure for some work.

And, it is not easy for many people to find the conversion
factors. Here are some:

Atmosphere -- 14.70 psi -- 1.058 tons per square foot--
29.92 inches of mercury -- 33.90 feet of water

Inches of water -- 0.03613 psi -- 0.07355 inches of
mercury-- 0.002458 atmospheres

By the way, the inches of water measure is based on 4 deg C
and mercury is based on 0 C.