Answer :
Final answer:
The velocity of flow in water mains is usually expressed in terms of cubic metres per hour.
Explanation:
The velocity of flow in water mains is usually expressed in terms of cubic metres per hour.
Flow rate is the volume of fluid passing through a point per unit time. In the case of water mains, the flow rate is commonly specified in terms of the volume of water passing through the pipes in a given time period.
For example, a water main might have a flow rate of 100 cubic metres per hour, indicating that 100 cubic metres of water pass through the pipes every hour.
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