| | Aerodynamics: World of Earth Science |
 | | These vortices are shed as the plane moves forward, creating a downward force or down-wash behind it. |
| | The downwash makes the airstream tilt downward and the resulting lift force tilt backward so that a net backward force or drag is created on the wing. |
| | This is known as induced drag or drag due to lift. |
| science.enotes.com /earth-science/aerodynamics (2175 words) |
