Aerodynamics means studying how air (or gas) travels around something moving through it. Streamlining to reduce drag in vehicles is a major field in aerodynamics. Aircraft design is another. The study of gases that are not in motion is called aerostatics. Aerodynamics comes from Aero (Air), and Dynamic (Moving).
One of the major goals of aerodynamics is to predict the aerodynamic forces on aircraft.
Weight is the force due to gravity and thrust is the force generated by the engine. Lift and drag are aerodynamic forces. Lift is positive upwards and drag is positive rearwards.
Aerodynamics is important in a number of applications other than aerospace engineering. It is a significant factor in any type of vehicle design, including automobiles. It is important in the prediction of forces and moments in sailing.
It is used in the design of small components such as hard drive heads. Civil engineers also use aerodynamics, and particularly aeroelasticity, to calculate wind loads in the design of large buildings and bridges.
Supersonic aerodynamic problems are those involving flow speeds greater than the speed of sound. Calculating the lift on the Concorde is an example of a supersonic aerodynamic problem. Supersonic flow behaves very differently from subsonic flow. The speed of sound can be considered the fastest speed that "information" can travel in the flow.
In 1726, Sir Isaac Newton became the first person to develop a theory of air resistance, making him one of the first aerodynamicists.
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Aerodynamics Facts for Kids. Kiddle Encyclopedia.