Definition -
Air resistance, also called drag, is the forces that are in opposition to the relative motion of an object through the air.Drag forces act opposite to the oncoming flow velocity. Drag, unlike other resistive forces, depends directly on velocity. Drag is the component of the net aerodynamic force acting opposite to the direction of the movement and the forces working perpendicular are called lift. Drag is overcome by thrust. In astrodynamics, atmospheric drag is both a positive and a negative force depending on the situation. It is a drain on fuel and efficiency during lift-off and a fuel savings when a spacecraft is returning from to Earth.
Types of drags -
There are three main types of drag in aerodynamics: lift induced, parasitic, and wave.
Each affects an objects ability to stay aloft as well as the power and fuel needed to keep it there.Lift induced -
Lift induced(induced)drag occurs as the result of the creation of lift on a three-dimensional lifting body.Parasitic drag -
Parasitic drag is caused by moving a solid object through a fluid. Parasitic drag is made up of multiple components including form drag and skin friction drag.Wave drag -
Wave drag (compressibility drag) is created by the presence of a body moving at high speed through a compressible fluid.In aerodynamics, wave drag consists of multiple components depending on the speed regime of the flight. In transonic flight (Mach 0.5 but less than 1.0), wave drag is the result of local supersonic flow are created.
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