🔍 Key Concepts

• Check valve function in a piping system • Difference between one-way flow and flow control/regulation • How air and liquid behave differently in valves and piping

💭 Think About

• Think about what engineers want to prevent when fluid should not be allowed to move backward in a system. • Which choice describes controlling the direction of flow, and which describe controlling the amount or rate of flow? • Do any of the options talk specifically about air versus liquid instead of direction of flow?

✅ Before You Answer

• Identify which option clearly refers to one-way flow rather than speed or volume of flow. • Eliminate any choices that focus on separating air from liquid instead of direction. • Ask yourself: in pump discharge lines and fuel lines, what is the main job of a check valve—direction, rate, or separation?