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[Phys-l] United States Geological Survey



For your amusement, check how the USGS applies the Bernoulli principle
in "Water Science for Kids":
http://ga.water.usgs.gov/edu/spcities.html

"The water pressure must be strong enough to sometimes go uphill to get
to your house, and as the water flows in the pipes, friction between the
water and the pipe walls reduces the water pressure. Water pressure is
kept up by gradually reducing the diameter of the pipe."

For more fun, check out this explanation about tides (also thanks to the
USGS):
http://sfports.wr.usgs.gov/SFPORTS/glossary.html#MLLW (*)

"There are two low tides in each tidal cycle (so usually two low tides
in each day). These two low tides are not quite the same height because
one tide is generated by the gravitational interaction with the sun
(which is small), and the other is generated by the gravitational
interaction with the moon (which is not so small)"

I believe that these are not typos but misconceptions...

Jacques


(*) I have emailed the USGS about this 2.5 years ago with no success.
Maybe a few more emails would help?