Considering subsonic incompressible airflow through a Venturi, which statement is correct?

• A. Both statements are true
• B. Only statement 1 is true
• C. Only statement 2 is true
• D. Neither statement is true

Answer: (C)

In this situation, the key idea is how velocity, pressure, and area relate in a Venturi with subsonic incompressible flow. The flow must satisfy continuity, so when the cross-sectional area decreases at the throat, the velocity must increase to keep the volumetric flow rate the same. Because the flow is incompressible, density stays constant, and Bernoulli’s principle applies along a streamline: the sum of static pressure and dynamic pressure stays constant. As velocity rises from the wider section to the throat, the static pressure must fall to compensate. So the correct takeaway is that the flow accelerates through the constriction while the static pressure decreases there. Statements that claim pressure increases with speed or that density changes would contradict this steady, incompressible, subsonic behavior.