Pressure is created by the_____.

• A. Pump
• B. Reservoir
• C. Resistance to flow
• D. Flow meter

Answer: (C)

Pressure comes from the flow being resisted. The pump adds energy to move fluid, but the pressure in the line builds as that fluid is forced through restrictions—valves, narrow passages, fittings, or any downstream impedance. The resistance converts the pump’s energy into pressure upstream of the restriction. If there were no resistance, the fluid would flow with little pressure. The reservoir mainly stores fluid and helps maintain supply, while a flow meter only measures flow; neither alone creates pressure. Think of a hose: pressure rises when you partially cover the nozzle—the resistance to flow is what creates the pressure.