Answer: The buoyant force equals its weight.
- A The buoyant force equals its weight
- B Its density equals the fluid density
- C Its volume exceeds the fluid volume
- D The fluid pressure equals atmospheric pressure
Correct answer: A. The buoyant force equals its weight
Explanation: Floating condition: F<sub>buoyancy</sub> = Weight. This means ρ_fluid × V<sub>submerged</sub> × g = m × g. For complete submersion: ρ_object = ρ_fluid.
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.