Which term describes pressure when water is at rest in the system?

• A. Static pressure
• B. Dynamic pressure
• C. Total pressure
• D. Hydrostatic pressure

Answer: (A)

When water isn’t moving, all the pressure you measure comes from the fluid’s weight and position, not from motion. That means dynamic pressure, which depends on velocity, is zero. The remaining pressure is static pressure, which in a still fluid aligns with what we call hydrostatic pressure—the pressure that increases with depth due to the water column. In irrigation practice, static pressure is the pressure you read with no flow (the pressure in the system when it’s at rest), and when flow starts, some of that static pressure is converted to dynamic pressure, while the total pressure is the sum of both. So the term for pressure in a resting system is static pressure.