- published: 21 Nov 2014
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A wing is an appendage with a surface that produces lift for flight or propulsion through the atmosphere, or through another gaseous or liquid fluid. A wing is an airfoil, which has a streamlined cross-sectional shape producing a useful lift to drag ratio.
The word "wing" from the Old Norse vængr for many centuries referred mainly to the foremost limbs of birds (in addition to the architectural aisle.) But in recent centuries the word's meaning has extended to include lift producing appendages of insects, bats, pterosaurs, boomerangs, some sail boats and aircraft.
"Wing" can also mean an inverted airfoil on a race car that generates a downward force to increase traction.
Various species of penguins and other flighted or flightless water birds such as auks, cormorants, guillemots, shearwaters, eider and scoter ducks and diving petrels are avid swimmers, and use their wings to propel through water.
A wing's aerodynamic quality is expressed as its lift-to-drag ratio. The lift a wing generates at a given speed and angle of attack can be one to two orders of magnitude greater than the total drag on the wing. A high lift-to-drag ratio requires a significantly smaller thrust to propel the wings through the air at sufficient lift.
Michelle LaVaughn Robinson Obama (born January 17, 1964) is the wife of the 44th and incumbent President of the United States, Barack Obama, and is the first African-American First Lady of the United States. Raised on the South Side of Chicago, Obama attended Princeton University and Harvard Law School before returning to Chicago and to work at the law firm Sidley Austin, where she met her future husband. Subsequently, she worked as part of the staff of Chicago mayor Richard M. Daley, and for the University of Chicago Medical Center.
Throughout 2007 and 2008, she helped campaign for her husband's presidential bid and delivered a keynote address at the 2008 Democratic National Convention. She is the mother of two daughters, Malia and Sasha, and is the sister of Craig Robinson, men's basketball coach at Oregon State University. As the wife of a Senator, and later the First Lady, she has become a fashion icon and role model for women, and an advocate for poverty awareness, nutrition and healthy eating.