Name: Vladimir L.
I am doing an experiment on hydraulics. The question I
am trying to answer is: What is the relationship between pressure and
tube diameter for a flow of liquid? I wanted to see if there is more
water pressure in a tube with a large diameter or a tube with a small
diameter. The large diameter tube had more pressure, Why?
What you are looking into is know as Pascal's Principle of Fluids.
Understand that a fluid is generally defined as a gas or liquid that is
contained. So, a fluid can be air, water, oil, etc. So if we have a fluid
in a contained space and pressure is applied to the fluid, Pascal's
Principle states that this pressure is transmitted through the fluid
undiminished with equal force on equal areas. The key words are equal force
on equal areas. If the areas are different, the forces will be different
and thus the pressures different. Pressure is defined as force per unit
area, and area is related to the diameter of the tube. So, I recommend that
you go to your local library and look for a book on hydraulics to get an
idea what Pascal's Principle (or some books may call it Pascal's Law) is.
Ask your librarian to help you find a book that is less mathematical and
more technical so you can get a better idea on how things work without all
of the theory. Please feel free to write back if you have more questions.
It sounds like a really good experiment.
Thanks for using Newton.
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Update: June 2012