Answer: Air flows faster above the wing (lower pressure) than below it.
- A Air flows faster above the wing (lower pressure) than below it
- B The wing's trailing edge pushes a downward jet of air with no pressure change
- C The wing is tilted so gravity components add to lift
- D Engine thrust is redirected vertically beneath the wing
Correct answer: A. Air flows faster above the wing (lower pressure) than below it
Explanation: By Bernoulli's principle, faster-moving air above the wing has lower pressure than slower-moving air below. The pressure difference creates an upward lift force.
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.