Newton's Laws, Pitched Wings, and "Lift"
The aerodynamic lift produced by the motion of a pitched, or tilted, wing moving through
air can be understood directly through Newton's
Laws of Motion.
Consider a pitched wing moving through stationary air at a constant speed, v. From
the point of view of the wing, it is not moving. Rather, the air is rushing by it with net
speed v in the opposite direction.
Air is made up of many molecules and atoms that follow Newton's Laws of Motion. Newton's
second law says that each molecule hitting the wing experiences an acceleration proportional
to the force of contact, and inversely proportional to its own mass.*
Newton's third law tells us that the wing experiences a force that is equal in size but
opposite in direction to that felt by the molecule.** While an individual collision of a
molecule has little effect, putting billions of billions of impacts together each second
does have a real effect - known as lift.