What creates lift?

What creates lift?

• A. The forward thrust produced by engines
• B. The upward force generated by the wings
• C. Air resistance that slows the aircraft
• D. Gravity acting on the mass

Answer: (B)

Lift is the upward force generated by the wings as air flows around them. The wing’s shape and its angle to the oncoming air cause air to move faster over the top surface than beneath it, creating lower pressure on top and higher pressure on the bottom. At the same time, the wing deflects air downward; by Newton’s third law, the air pushes the wing upward, producing lift. This upward force must balance the airplane’s weight for steady, level flight. Engine thrust moves the airplane forward, but it does not create lift. Air resistance (drag) is a backward force that slows the aircraft, not lift. Gravity acts downward on the aircraft’s mass, pulling it toward the Earth.

Lift is the upward force generated by the wings as air flows around them. The wing’s shape and its angle to the oncoming air cause air to move faster over the top surface than beneath it, creating lower pressure on top and higher pressure on the bottom. At the same time, the wing deflects air downward; by Newton’s third law, the air pushes the wing upward, producing lift. This upward force must balance the airplane’s weight for steady, level flight.

Engine thrust moves the airplane forward, but it does not create lift. Air resistance (drag) is a backward force that slows the aircraft, not lift. Gravity acts downward on the aircraft’s mass, pulling it toward the Earth.