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Is lift fully understood?
Scientifically speaking, lift is perfectly understood. Lift is merely the vertical component of force generated by a body moving through a fluid. And we know perfectly well how to calculate forces on a body moving through a fluid since the Navier-Stokes equations was published in 1822.
Do we understand lift?
We understand lift by empathy: We feel it. In viscosity-free air there would be no drag and no lift. Any force produced as the wing pushed the air aside would be exactly neutralized as the air sprang back into place. Obviously, this was not what was happening, since real wings produce real lift and real drag.
Do we know how lift is generated?
Lift is a mechanical force. It is generated by the interaction and contact of a solid body with a fluid (liquid or gas). It is not generated by a force field, in the sense of a gravitational field,or an electromagnetic field, where one object can affect another object without being in physical contact.
What is the correct lift theory?
The theory states that a wing keeps an airplane up by pushing the air down. Air has mass, and from Newton’s third law it follows that the wing’s downward push results in an equal and opposite push back upward, which is lift.
What is the formula for lift force?
The lift equation states that lift L is equal to the lift coefficient Cl times the density r times half of the velocity V squared times the wing area A. For given air conditions, shape, and inclination of the object, we have to determine a value for Cl to determine the lift.
How is the physical description of lift wrong?
The major disadvantage is that it relies on the “principle of equal transit times” which is wrong. This description focuses on the shape of the wing and prevents one from understanding such important phenomena as inverted flight, power, ground effect, and the dependence of lift on the angle of attack of the wing.
Are there any explanations for the generation of lift?
There are many explanations for the generation of lift found in encyclopedias, in basic physics textbooks, and on Web sites. Unfortunately, many of the explanations are misleading and incorrect. Theories on the generation of lift have become a source of great controversy and a topic for heated arguments.
How is the lift of an airplane generated?
For younger students, a simpler explanation of the information on this page is available on the Kid’s Page. Lift is the force that directly opposes the weight of an airplane and holds the airplane in the air. Lift is generated by every part of the airplane, but most of the lift on a normal airliner is generated by the wings.
Because lift is a force, it is a vector quantity , having both a magnitude and a direction associated with it. Lift acts through the center of pressure of the object and is directed perpendicular to the flow direction.