zzangga asked in Science & MathematicsPhysics · 1 decade ago

# Could someone explain the following question?

The concept of how air pressure changes with respect to change in air velocity. Relate this to the lift on an aircraft wings.

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• 1 decade ago

As an object moves through air, resistance is built up as a result of the air molecules impacting it. The faster the object, the more pressure is built up on the object. If the object is aero-dynamic, at some point depending on weight and trajectory, the object will be lifted by the combination of velocity and resistance. This is refered to as the Zeffran Cochran theory of molecular resistance.

Source(s): S.F.Com Flight Basic Manual - NCC-1701 :)
• 1 decade ago

this is based on Bernoulli's principle which states that, for a streamline fluid(air can be considered to be a fluid), the sum of pressure and velocity is a constant.so when air pressure decreases, velocity has to increase and vice verse so that their sum is still a constant.

it might be easier to understand in terms of a buildings roof being thrown into the air when a cyclone occurs. since the air velocity is very high over the roof, the pressure under the roof builds up thus lifting up the roof. this is what happens in air crafts as well.when the aircraft wings come down, the pressure under the wings increase& it gets propelled uwards, and when the wings lift up, the pressure decreases & it comes down

• Steve
Lv 7

Daniel Bernoulli discovered that increasing the velocity of an airflow would lower its pressure. An airplane's wing is shaped and aligned with the oncoming air such that the air has a longer path to go over the top of the wing, which means its average velocity is higher and pressure lower. The difference in pressure from the lower to upper surface of the wing times the area of the wing gives the gross lift.

• 1 decade ago

This is Bernoulis principle. In simple terms, when the velocity of as a velocity of a fluid increases, the pressure it exert decreases.Because the air moves faster over the top of the wing, than the bottoms, a high pressure area is formed below the wing, and low pressure above the wing, causing the plane to have lift.