Answer: equally in all directions.
- A only vertically downward
- B only along the container walls
- C only vertically upward
- D equally in all directions
Correct answer: D. equally in all directions
Explanation: Pressure in a static fluid is isotropic; it acts equally in every direction at a given point.
Since the same volume of fluid must pass every cross-section per second (continuity), the fluid speeds up where the pipe narrows; Bernoulli's equation then says this faster-moving fluid has lower pressure - the principle behind a venturi meter and an aircraft wing's lift.
Concept context
Pressure, buoyancy, Bernoulli equation, viscosity, and surface tension.