AERODYNAMICS  
INTRODUCTION

Aerodynamic is derived from the two Greek words ; aerios and dynamis. The meaning of aerios is the air, and the meaning of dynamis is the forces. It is the science of forces and the resulting motion of objects through the air. Aerodynamics has thousands years of history, although flying in a heavier-than-air machine has been possible only in the last hundred years. The main theory of aerodynamics is that it explains how an airplane is able to fly. Aerodynamics is specially useful for aerospace engineering. Besides this, automobile , structural engineering are also using it.

How does Aerodynamics work ?

There are four forces of flight which helps an object to move through the air. They are , weight, lift, drag and thrust. These forces produce the actions to make an object move up and down, and faster or slower.


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The four forces of flight help an object move through the air. Image Credit: NASA

What Are the Four Forces of Flight?

  1. Weight is the gravity of earth and it is a kind of force helps to pull down on objects. It is the opposite of lift force. The weight of an object controls how strong the push has to be.


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Weight comes from gravity pulling down on objects. Image Credit: NASA

2 . Lift is a kind of force that helps to push and lets something move up. An aircraft needs lift to move upward. Lift comes from aircraft's wings . To move the aircraft upward, it must have more lift than weight. When the force of lift is greater than the force of gravity, the airplane is able to fly.

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An airfoil shape is especially good at producing lift. Image Credit: NASA

3 . Drag is a force which tries to slow something down. It makes hard for an object to move, the object can slow down. The amount of drag depends on the shape of an object. For example, round surfaces have less drag than flat ones. Narrow surfaces usually have less drag than wide ones. The more air that hits a surface, the more drag it makes.


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As an object moves through the air, it pushes aside air molecules. Image Credit: NASA

4. Thrust is another important force which helps to move the object . It is opposite of drag. To keep moving forward the aircraft , it must have more thrust than drag. The small airplane gets its thrust from a propeller, a larger airplane gets its thrust from jet engines.


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Thrust is the force that moves an aircraft forward. Image Credit: NASA












CONCLUSION
Aerodynamics is the science of study of the air and forces. Lift, weight, drag and thrust are the major forces that react with the air and produce such a strong forces by which the plane can fly in the sky and land on the ground. Anything that moves through air reacts to aerodynamics. Besides, aeroplanes, Aerodynamics can be used on vehicles, a rocket blasting off the launch pad and a kite in the sky. It is also used in structural engineering to calculate wind loads in the design of large buildings and bridges.

Bibliography

http://www.nasa.gov/audience/forstudents/k-4/stories/what-is-aerodynamics-k4.html

http://en.wikipedia.org/wiki/Aerodynamics

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