Calculating Water Speed & Volume from Pressure

AI Thread Summary
To calculate the speed of water from well pressure, energy conservation principles can be applied. The kinetic energy of the water at the well's output is equal to the potential energy at its highest point. By setting the equations for kinetic and potential energy equal, the formula v = (2gh)^(1/2) can be derived. Given the height of 12.6 meters, the resulting speed of the water is calculated to be 15.7 m/s. This method effectively determines both the speed and volume of water flow based on pressure measurements.
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Maybe this should be in the math section, I'm not sure. I have this friend that works in the water industry that tells me my town runs off of 3 wells that each have the pressure to shoot a stream of water 8" diameter 12.6m up. I was wondering from this information how I could figure out how fast that water must be moving and in turn the volume. So how could I go about doing this?
 
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You can use energy conservation to solve that.
Take the potential energy as 0 at the output of the well.

The energy of the stream at the output of the well is

\frac{Mv^2}{2}​

(no potential energy, only kinetic energy, speed is v, M is the mass of a piece of water)

The energy of the stream at the highest reach, when the velocity drops to zero is:

Mg​

(no kinetic energy, only potential energy)

Since energy is conserved during the motion (without air friction), we have:

\frac{Mv^2}{2}=Mgh​
(h is the highest reach)

We get easily:

\frac{v^2}{2}=gh​
v={(2gh)}^{1/2}​

Finally, this gives v = 15.7 m/s .
 
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