The diagram below shows a water service pipe feeding a tank.

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The pressure available from the main is 350kPa.
The service pipe length is 62m and the water requirement at the tank entry is 36 litres/minute.
Using the formula q225L = d5H
where q = discharge in litres per second
d = ID in centimetres
H = head of water in metres
L = length in metres
calculate the internal diameter of the water service pipe from the utility water main to the tank.
Use the conversion 1 metre head = 10kPa.



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