What is defined as the force exerted by a fluid at rest?

The force exerted by a fluid at rest is defined as static pressure. This type of pressure is relevant in scenarios where the fluid is contained and not in motion, such as in a water supply system or a closed tank. Static pressure is measured in units such as pascals or pounds per square inch, and it represents the potential energy of the fluid due to its height and volume, acting uniformly in all directions.

Dynamic pressure, in contrast, is associated with fluid in motion and is derived from the velocity of the fluid. Hydraulic pressure is a more general term that can refer to pressure in a hydraulic system, which may include both static and dynamic components depending on system operation. Atmospheric pressure refers to the weight of the air above a given point and is not specific to fluids at rest but rather relevant to all standards of pressure measurement in the atmosphere. Understanding static pressure is crucial in backflow prevention systems as it helps ensure proper function and safety in fluid delivery systems.