2b – Drag
The Drag force is the resistance of any fluid (water or air).
When the plane is flying, the air is somehow slowing down the plane.
For aircraft, drag is largely produced by the collision of it’s skin with air particles.
Exemple: do you run faster the wind facing you or the wind in your back?
As aircraft are very fast reducing drag is very important. That is why the shape of the plane is design to reduce drag as much as possible: this is called being “aerodynamic”.
A bit of maths: Drag relates to the Square of the velocity (D ~ V²). That means that if velocity is double, drag is four times as high.
Question: How much larger is the drag of an aircraft moving at 150 m/s compared to an aircraft moving at 100 m/s?
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