Principles of Flight: Chapter 4 Introduction

78 percent nitrogen, 21 percent oxygen, and 1 percent other gases

To use or counteract the natural forces acting on the aircraft

Understanding the performance characteristics of the aircraft

<p>It has mass, weight, and indefinite shape</p> Signup and view all the answers

<p>Argon or helium</p> Signup and view all the answers

<p>To control an aircraft</p> Signup and view all the answers

<p>Viscosity is the property of a fluid that causes it to resist flowing.</p> Signup and view all the answers

<p>An example of a high-viscosity fluid is grease, and an example of a low-viscosity fluid is motor oil.</p> Signup and view all the answers

<p>Friction is the resistance that one surface or object encounters when moving over another.</p> Signup and view all the answers

<p>The roughness of a surface causes resistance and slows the velocity of the fluid flowing over it.</p> Signup and view all the answers

<p>Water flows more freely due to its lower viscosity, while oil flows much more slowly due to its higher viscosity.</p> Signup and view all the answers

<p>Air, being a fluid, has viscosity properties, so it resists flow around any object to some extent.</p> Signup and view all the answers

<p>Air molecules adhere to the surface of the wing due to friction caused by the surface roughness.</p> Signup and view all the answers

<p>Surface roughness causes resistance and slows the velocity of the air flowing over the wing.</p> Signup and view all the answers

<p>The rough surface ramp impedes the flow of the fluid due to resistance from the surface (friction).</p> Signup and view all the answers

<p>Understanding the fluid properties of air is essential to understanding the principles of flight.</p> Signup and view all the answers