What is the relationship between the pressure in the venturi throat and the velocity of the air passing through it?

The correct answer highlights the principle described by Bernoulli's equation, which relates the pressure, velocity, and height in fluid dynamics. In a venturi meter, as air (or any fluid) flows through a constricted section known as the throat, its velocity increases due to the conservation of mass. According to Bernoulli's principle, there is an inverse relationship between pressure and velocity: as the velocity of the fluid increases, the pressure in that region decreases.

This inverse relationship is crucial for various applications, including fuel metering systems, where understanding the dynamics of airflow and pressure helps with accurate measurements and efficient system design. When the cross-sectional area decreases (as it does in the venturi throat), the speed of the air must increase to maintain a constant flow rate, leading to a drop in pressure in that throat area.

The other relationships suggested do not align with this principle. For instance, the idea that pressure is directly proportional to velocity would contradict the fundamental understanding of fluid dynamics in constricted flows. Similarly, stating that pressure and velocity are independent does not hold true in the context of flow through a venturi. Lastly, the claim that velocity affects pressure only at high speeds neglects the omnipresent effect of flow dynamics at all