FAA Aviation Mechanic General (AMG)Physics, Math and Fluid LinesMedium
Air flows through the constricted throat of a carburetor venturi at increased velocity. According to Bernoulli's principle, what happens to the static pressure at the throat compared to the wider section of the venturi?
- AStatic pressure remains unchanged
- BStatic pressure increases
- CStatic pressure decreases
- DStatic pressure becomes equal to total pressure
Show answer & explanationAnswer & explanation
Correct answer: C. Static pressure decreases
Bernoulli's principle states that as fluid velocity increases through a constriction, static pressure decreases, keeping total energy constant.
Why the other options are wrong
- A. Incorrect since velocity change directly affects static pressure.
- B. Opposite of Bernoulli's principle relationship.
- D. Confuses total pressure with static pressure, which are different quantities.
Bernoulli's Principle
As the velocity of a fluid increases, its static pressure decreases, assuming total energy remains constant.
- Basis for venturi and carburetor operation
- Also explains lift generation over an airfoil
- Total pressure = static pressure + dynamic pressure
- Velocity and static pressure are inversely related
Memory trick: Speed up the flow, pressure goes low.