EASA MODULE 02 PDF

FOR B1 & B2 CERTIFICATION Module 02 PHYSICS Aviation Maintenance Technician Certificat...

FOR B1 & B2 CERTIFICATION Module 02 PHYSICS Aviation Maintenance Technician Certification Series - Matter - Mechanics - Thermodynamics - Optics (Light) - Wave Motion and Sound www.amequestionpaper.in > Visit our website to download all latest EASA / DGCA CAR 66 Module examination Question papers and study material  EASA Part-66 Aviation Maintenance Technician Certification Series NO COST REVISION/UPDATE SUBSCRIPTION PROGRAM Complete EASA Part-66 Aviation Maintenance Technician Certification Series NO COST REVISION/UPDATE PROGRAM Aircraft Technical Book Company is offering a revision/update program to our customers who purchase an EASA Module from the EASA Aviation Maintenance Technician Certification Series. The update is good for two (2) years from time of registration of any EASA Module or EASA bundled kits. If a revision occurs within two (2) years from date of registration, we will send you the revised pages FREE of cost to the registered email. Go to the link provided at the bottom of this page and fill out the form to be included in the EASA Revision/Update Subscription Program. In an effort to provide quality customer service please let us know if your email you register with changes so we can update our records. If you have any questions about this process please send an email to: [email protected] HERE’S HOW IT WORKS 1. All EASA Module Series textbooks contain an EASA subscription page explaining the subscription update process and provide a web site link to register for the EASA Revision/Update Subscription Program. 2. Go to the link provided below and fill out the web based form with your first and last name, current email address, and school if applicable. 3. From the time of purchase, if a revision occurs to the Module you have registered for, a revised PDF file containing the pages with edits will be sent to the registered email provided. 4. Please note that we try to keep our records as current as possible. If your email address provided at time of registration changes please let us know as soon as possible so we can update your account. 5. This service is FREE of charge for two (2) years from date of registration. LINK TO REGISTER FOR REVISION/UPDATE PROGRAM http://www.actechbooks.com/easasub/m02  www.amequestionpaper.in > Visit our website to download all latest EASA / DGCA CAR 66 Module examination Question papers and study material  MODULE 02 FOR B1 & B2 CERTIFICATION PHYSICS www.amequestionpaper.in > Visit our website to download all latest EASA / DGCA CAR 66 Module examination Question papers and study material Aviation Maintenance Technician Certification Series 72413 U.S. Hwy 40 Tabernash, CO 80478-0270 USA www.actechbooks.com +1 970 726-5111  AVAILABLE IN Printed Edition and Electronic (eBook) Format AVIATION MAINTENANCE TECHNICIAN CERTIFICATION SERIES Author Thomas Forenz Layout/Design Michael Amrine Copyright © 2016 — Aircraft Technical Book Company. All Rights Reserved. No part of this publication may be reproduced, stored in a retrieval system, transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of the publisher. To order books or for Customer Service, please call +1 970 726-5111. www.actechbooks.com Printed in the United States of America  WELCOME The publishers of this Aviation Maintenance Technician Certification Series welcome you to the world of aviation maintenance. As you move towards EASA certification, you are required to gain suitable knowledge and experience in your chosen area. Qualification on basic subjects for each aircraft maintenance license category or subcategory is accomplished in accordance with the following matrix. Where applicable, subjects are indicated by an "X" in the column below the license heading. For other educational tools created to prepare candidates for licensure, contact Aircraft Technical Book Company. We wish you good luck and success in your studies and in your aviation career! REVISION LOG VERSION EFFECTIVE DATE DESCRIPTION OF CHANGE 001 2013 12 Original Issue 002 2016 11 Format Update www.amequestionpaper.in > Visit our website to download all latest EASA / DGCA CAR 66 Module examination Question papers and study material iii  FORWARD PART-66 and the Acceptable Means of Compliance (AMC) and Guidance Material (GM) of the European Aviation Safety Agency (EASA) Regulation (EC) No. 1321/2014, Appendix 1 to the Implementing Rules establishes the Basic Knowledge Requirements for those seeking an aircraft maintenance license. The information in this Module of the Aviation Maintenance Technical Certification Series published by the Aircraft Technical Book Company meets or exceeds the breadth and depth of knowledge subject matter referenced in Appendix 1 of the Implementing Rules. However, the order of the material presented is at the discretion of the editor in an effort to convey the required knowledge in the most sequential and comprehensible manner. Knowledge levels required for Category A1, B1, B2, and B3 aircraft maintenance licenses remain unchanged from those listed in Appendix 1 Basic Knowledge Requirements. Tables from Appendix 1 Basic Knowledge Requirements are reproduced at the beginning of each module in the series and again at the beginning of each Sub-Module. How numbers are written in this book: This book uses the International Civil Aviation Organization (ICAO) standard of writing numbers. This method displays large numbers by adding a space between each group of 3 digits. This is opposed to the American method which uses commas and the European method which uses periods. For example, the number one million is expressed as so: ICAO Standard 1 000 000 European Standard 1.000.000 American Standard 1,000,000 SI Units: The International System of Units (SI) developed and maintained by the General Conference of Weights and Measures (CGPM) shall be used as the standard system of units of measurement for all aspects of international civil aviation air and ground operations. Prefixes: The prefixes and symbols listed in the table below shall be used to form names and symbols of the decimal multiples and submultiples of International System of Units (SI) units. MULTIPLICATION FACTOR PReFIx SyMbOL 1 000 000 000 000 000 000 = 101⁸ exa E 1 000 000 000 000 000 = 101⁵ peta P 1 000 000 000 000 = 1012 tera T 1 000 000 000 = 10⁹ giga G 1 000 000 = 10⁶ mega M 1 000 = 103 kilo k 100 = 102 hecto h 10 = 101 deca da 0.1 =10-1 deci d 0.01 = 10-2 centi c 0.001 = 10-3 milli m 0.000 001 = 10-⁶ micro µ 0.000 000 001 = 10-⁹ nano n 0.000 000 000 001 = 10-12 pico p 0.000 000 000 000 001 = 10-1⁵ femto f 0.000 000 000 000 000 001 = 10-1⁸ atto a International System of Units (SI) Prefixes  EASA LICENSE CATEGORY CHART A1 B1.1 B1.2 B1.3 B2 Module number and title Airplane Airplane Airplane Helicopter Avionics Turbine Turbine Piston Turbine 1 Mathematics X X X X X 2 Physics X X X X X 3 Electrical Fundamentals X X X X X 4 Electronic Fundamentals X X X X 5 Digital Techniques / Electronic Instrument Systems X X X X X 6 Materials and Hardware X X X X X 7A Maintenance Practices X X X X X 8 Basic Aerodynamics X X X X X 9A Human Factors X X X X X 10 Aviation Legislation X X X X X 11A Turbine Aeroplane Aerodynamics, Structures and Systems X X 11B Piston Aeroplane Aerodynamics, Structures and Systems X 12 Helicopter Aerodynamics, Structures and Systems X 13 Aircraft Aerodynamics, Structures and Systems X 14 Propulsion X 15 Gas Turbine Engine X X X 16 Piston Engine X 17A Propeller X X X MODULE 02 SYLLABUS AS OUTLINED IN PART-66, APPENDIX 1. LEVELS CERTIFICATION CATEGORY ¦ B1 B2 Sub-Module 01 - Matter Nature of matter: the chemical elements, structure of atoms, molecules; 1 1 Chemical compounds. States: solid, liquid and gaseous; Changes between states. Sub-Module 02 - Mechanics 2.2.1 - Statics Forces, moments and couples, representation as vectors; 2 1 Centre of gravity; Elements of theory of stress, strain and elasticity: tension, compression, shear and torsion; Nature and properties of solid, fluid and gas; Pressure and buoyancy in liquids (barometers). 2.2.2 - Kinetics Linear movement: uniform motion in a straight line, motion under constant acceleration 2 1 (motion under gravity); Rotational movement: uniform circular motion (centrifugal/centripetal forces); Periodic motion: pendular movement; Module 02 - Physics v  LEVELS CERTIFICATION CATEGORY ¦ B1 B2 Simple theory of vibration, harmonics and resonance; Velocity ratio, mechanical advantage and efficiency. 2.2.3 - Dynamics (a) Mass 2 1 Force, inertia, work, power, energy (potential, kinetic and total energy), heat, efficiency; (b) Momentum, conservation of momentum; 2 2 Impulse; Gyroscopic principles; Friction: nature and effects, coefficient of friction (rolling resistance). 2.2.4 - Fluid Dynamics (a) Specific gravity and density; 2 2 (b) Viscosity, fluid resistance, effects of streamlining; 2 1 Effects of compressibility on fluids; Static, dynamic and total pressure: Bernoulli's Theorem, venturi. Sub-Module 03 - Thermodynamics (a) Temperature: thermometers and temperature scales: Celsius, 2 2 Fahrenheit and Kelvin; Heat definition; (b) Heat capacity, specific heat; 2 2 Heat transfer: convection, radiation and conduction; Volumetric expansion; First and second law of thermodynamics; Gases: ideal gases laws; specific heat at constant volume and constant pressure, work done by expanding gas; Isothermal, adiabatic expansion and compression, engine cycles, constant volume and constant pressure, refrigerators and heat pumps; Latent heats of fusion and evaporation, thermal energy, heat of combustion. Sub-Module 04 - Optics (Light) Nature of light; speed of light; 2 2 Laws of reflection and refraction: reflection at plane surfaces, reflection by spherical mirrors, refraction, lenses; Fiber optics. Sub-Module 05 - Wave Motion and Sound Wave motion: mechanical waves, sinusoidal wave motion, interference phenomena, 2 2 standing waves; Sound: speed of sound, production of sound, intensity, pitch and quality, Doppler effect. vi Module 02 - Physics  CONTENTS PHYSICS Simple Machines‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.13 Welcome‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ iii Mechanical Advantage of Machines‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.13 Revision Log‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ iii The Lever‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.14 Forward‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ iv First Class Lever‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.14 Contents‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ vii Second Class Lever‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.14 Third Class Lever‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.15 SUB-MODULE 01 Single Fixed Pulley‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.15 MATTER Single Movable Pulley‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.15 Knowledge Requirements‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.1 Block and Tackle‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.16 Introduction‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.2 The Gear‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.16 Matter‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.2 Velocity Ratio‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.18 The Nature of Matter‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.2 Inclined Plane‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.19 Isotopes‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.3 The Wedge‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.20 States of Matter‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.5 Efficiency‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.20 Catalyst‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.6 Dynamics‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.20 Questions‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.7 Mass and Weight‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.20 Answers‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 1.8 Energy‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.20 Potential Energy‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.20 SUB-MODULE 02 Kinetic Energy‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.21 MECHANICS Force, Work, Power and Torque‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.21 Knowledge Requirements‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.1 Force‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.21 Statics‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.2 Work‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.21 Forces, Moments and Couples‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.2 Friction and Work‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.22 Center of Gravity‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.2 Static Friction‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.23 Elements of Theory of Stress‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.3 Sliding Friction‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.23 Strain‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.4 Rolling Friction‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.23 Nature and Properties of Matter‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.5 Power‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.24 Solid‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.5 Torque‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.24 Liquid‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.5 Heat and Efficiency‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.25 Gas‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.5 Momentum‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.25 Changes Between States‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.5 Gyroscopic Principles‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.26 Pressure and Buoyancy‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.6 Fluid Dynamics‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.28 Buoyancy‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.6 Density‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.28 Fluid Pressure‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.7 Specific Gravity‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.28 Kinetics‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.9 Fluid Mechanics‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.29 Motion‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.9 Pascal's Law‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.29 Uniform Motion‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.9 Bernoulli's Principle‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.31 Speed and Velocity‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.9 Viscosity‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.32 Acceleration‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.10 Streamlining‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.33 Newton's Laws of Motion‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.10 Questions‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.35 First Law‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.10 Answers‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.36 Second Law‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.10 Circular Motion‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.11 SUB-MODULE 03 Periodic Motion‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.12 THERMODYNAMICS Pendular‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.12 Knowledge Requirements‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.1 Vibration‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.12 Thermodynamics‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.2 Resonance‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 2.13 Heat‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.2 Module 02 - Physics vii  CONTENTS Heat Energy Units‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.2 SUB-MODULE 05 Temperature‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.3 WAVE MOTION AND SOUND Thermal Expansion/Contraction‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.3 Knowledge Requirements‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.1 Thermometers‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.4 Sound‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.2 Non-Electric‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.4 Wave Motion‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.2 Temperature Indicators‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.4 Speed of Sound‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.3 Electrical Temperature Measuring Indication‥‥‥‥‥ 3.5 Mach Number‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.3 Electrical Resistance Thermometer‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.5 Frequency of Sound‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.3 Ratiometer Electrical Resistance Thermometers‥‥‥ 3.6 Loudness‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.3 Thermocouple Temperature Indicators‥‥‥‥‥‥‥‥‥‥‥ 3.7 Measurement of Sound Intensity‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.4 Heat Transfer‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.9 Doppler Effect‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.4 Conduction‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.9 Questions‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.5 Convection‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.10 Answers‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 5.6 Radiation‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.10 Specific Heat‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.11 Acronym Index‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ A.1 Thermodynamic Laws‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.12 Index‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ I.1 Gas Laws‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.12 Notes‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ N.1 Boyle's Law‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.12 Charles' Law‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.13 General Gas Law‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.13 Dalton's Law‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.14 Ideal Gas Law‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.14 Work and Expanding Gases‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.14 Engine Cycles‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.14 Constant Volume‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.14 Constant Pressure‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.15 Heat of Combustion‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.16 Thermal Energy‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.16 Thermal Efficiency‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.16 Refrigeration‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.17 Questions‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.19 Answers‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 3.20 SUB-MODULE 04 OPTICS (LIGHT) Knowledge Requirements‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.1 The Nature of Light‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.2 Reflection‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.2 Refraction‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.3 Lenses‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.3 Fiber Optics‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.4 Cable Construction‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.4 Fiber modes‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.4 Termination and splicing‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.5 Fiber Optic Data Link‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.7 Questions‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.9 Answers‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 4.10 viii Module 02 - Physics  MATTER PART-66 SYLLABUS LEVELS CERTIFICATION CATEGORY ¦ B1 B2 Sub-Module 01 MATTER Knowledge Requirements 2.1 - Matter 1 1 Nature of matter: the chemical elements, structure of atoms, molecules; Chemical compounds. States: solid, liquid and gaseous; Changes between states. Level 1 A familiarization with the principal elements of the subject. Objectives: (a) The applicant should be familiar with the basic elements of the subject. (b) The applicant should be able to give a simple description of the whole subject, using common words and examples. (c) The applicant should be able to use typical terms. www.amequestionpaper.in > Visit our website to download all latest EASA / DGCA CAR 66 Module examination Question papers and study material Module 02 - Physics 1.1 INTRODUCTION Physics is the term applied to that area of knowledge Physics allows us to explain how engines work, how regarding the basic and fundamental nature of matter airplanes and helicopters fly, and countless other things and energy. It does not attempt to determine why related to the field of aviation and aerospace. In addition matter and energy behave as they do in their relation to to allowing us to explain the operation of the things physical phenomena, but rather how they behave. The around us, physics also allows us to quantify them. For people who maintain and repair aircraft should have a example, through the use of physics we can explain what knowledge of basic physics. the concept of thrust means for a jet engine, and then follow it up by mathematically calculating the pounds of thrust being created. MATTER Matter is the foundation for any discussion of physics. Matter is what all things are made of; whatever occupies space, has mass, and is perceptible to the senses in some way. According to the Law of Conservation, matter Proton cannot be created or destroyed, but it is possible to change its physical state. When liquid gasoline vaporizes Electron and mixes with air, and then burns, it might seem that Nucleus this piece of matter has disappeared and no longer exists. Although it no longer exists in the state of liquid gasoline, the matter still exists in the form of the gases given off by the burning fuel. Electron Shell Neutron THE NATURE OF MATTER All matter is made up of atoms. An atom is the smallest unit of matter that establishes the unique characteristics of a substance. There are over 100 different kinds of Figure 1-1. An atom and its sub-atomic particles. matter each made up of atoms with different physical attributes. These varied and unique kinds of matter are Generally, each atom contains the same number of called elements. They cannot be further broken down electrons and neutrons as the atom has protons. However, into simpler substances without losing their unique the number of these particles that each atom contains is identity. what causes the elements to be different. For example, an atom of hydrogen, has one proton, one neutron and one Atoms of different elements are similar to each other in electron. It is the simplest element. An atom of Oxygen, that they contain the same basic parts. An atom has a has eight protons, eight neutrons and eight electrons. nucleus within the nucleus are subatomic particles. One Copper has 29 of each of these subatomic particles and or more protons are found at the nucleus of all atoms. so forth. The number of subatomic particles that each The proton has a positive electrical charge. One or more atom contains defines the type of element it is and its neutrons are also found at the nucleus of all atoms. A inherent properties. The mass of an atom is related to neutron has no electrical charge. Orbiting around the how many characteristic subatomic particles make up nucleus is a third kind of subatomic particle called an the atom of each element. electron. An electron has a negative electrical charge. Electrons are configured around the nucleus in orderly, Elements are assigned an atomic number according concentric rings known as shells. Figure 1-1 illustrates to how many protons are found at the nucleus of their the basic structure and components of atoms. atoms. Each element also has a distinctive 1, 2, or 3 letter abbreviation. The elements are arrange in a table 1.2 Module 02 - Physics known as the periodic table of elements. The table nucleus. The material is chemically disposed to combine groups the elements by periods horizontally and by with other materials or other identical atoms to fill in groups vertically to show similar characteristics of the the unstable valence configuration and bring the number MATTER elements. (Figure 1-2) of electrons in the valence shell to maximum. Two or more substances may share the electrons in their valence Atoms of the same or different elements may chemically shells and form a covalent bond. A covalent bond is the bond to form a molecule. When two or more atoms of method by which atoms complete their valence shells by the same element bond to form a molecule, it will have sharing valence electrons with other atoms. Molecules the inherent properties of that element. When atoms are formed this way. of different elements bond to form a molecule, the molecule has properties and characteristics completely Electrons in incomplete valence shells may also move different than those of each individual elements that freely from valence shell to valence shell of different comprise it. A water molecule, for example, is made up atoms or compounds. In this case, these are known as of two hydrogen atoms and one oxygen atom. Water has free electrons. As stated, the movement of electrons its own unique properties that are completely different is known as electric current or current f low. When than those of hydrogen or oxygen alone. electrons move freely from atom to atom or compound to compound, the substance is known as a conductor. When atoms bond to form molecules, they share (Figure 1-5) electrons. The closest shell to the nucleus can only contain two orbiting electrons. If the atom has more than two Materials made up of t wo or more elements that electrons, they are found in the next orbital shell farther have chemically bonded are known as compounds. away from the nucleus. This second shell can only hold Compounds have properties different than the elements eight electrons. If the atom has more than ten electrons from which they are made. They can only be separated (2 first shell + 8 second shell), they orbit in a third shell through chemical reaction. They have a unique chemical farther out from the nucleus. This third shell is filled with structure with a fixed ratio of atoms of different elements up to eight electrons and then a fourth shell starts to fill that are bonded together chemically. Compounds should if the element still has more electrons. However, when not be confused with mixtures. Mixtures are atoms and the fourth shell contains eight electrons, the number of molecules that are physically mixed together but are not electrons in the third shell begins to increase again until chemically bonded. The properties and characteristics a maximum of 18 is reached. (Figure 1-3) of a mixture are closely related or dependent on the properties of the individual constituents. Mixtures can The outer-most orbital shell of any atom's electrons is usually be separated by filtering, evaporation or some called the valence shell. The number of electrons in other mechanical means. the valence shell determines the chemical bonding properties of the material as well as other characteristics ISOTOPES such as conductivity. When the valence shell has the W hen atoms of the same element have different maximum number of electrons, it is complete and the numbers of neutrons, they are called isotopes. Because electrons tend to be bound strongly to the nucleus. of the differing numbers of neutrons, various isotopes Materials with this characteristic are chemically stable. of the same element have different masses. Mass is the It takes a large amount of force to move the electrons word for how much matter something has and therefore in this situation from one atom valence shell to that how much it weighs. Because different isotopes have of another. Since the movement of electrons is called different numbers of neutrons, they do not all weigh electric current, substances with complete valence shells the same. Different isotopes of the same element have are known as good insulators because they resist the flow the same atomic number because they have the same of electrons (electricity). (Figure 1-4) number of protons. The atomic number is decided by the number of protons. (Figure 1-6) In atoms with an incomplete valence shell, that is, those without the maximum number of electrons in their valence shell, the electrons are bound less strongly to the Module 02 - Physics 1.3  Figure 1-2. The periodic table of elements. 1.4 Module 02 - Physics  Shell or Orbit Number 1 2 3 4 5 Maximum Number Of Electrons 2 8 18 32 50 MATTER Figure 1-3. Maximum number of electrons in each orbital shell of an atom. He Ne Ar Kr Al Cu Ag Au Felium Neon Argon Krypton Figure 1-4. Elements with full valence shells are good insulators. Aluminum Copper Silver Gold Most insulators used in aviation are compounds of two or more Figure 1-5. The valence shells of elements that are elements that share electrons to fill their valence shells. common conductors have one (or three) electrons. Figure 1-6. Isotopes of hydrogen. Isotopes of the same element also have the same number maintenance professional. The compound(s) from which of electrons and the same electronic structure. Because a substance is made do not change, regardless of the how an atom acts is decided by its electronic structure, state of matter. Atoms and molecules that make up a isotopes are almost the same chemically, but they are substance are always in a state of motion due to heat different physically because of their different masses. energy in the material. The physical state of matter is related to the degree of motion between these particles Hydrogen, the most common element, has three with solids having the least motion and gases and common isotopes. Its most common isotope with only plasma having the most. one proton and no neutrons is called protium (1H). A hydrogen atom with one proton and one neutron (atomic Plasma is a unique state of matter comprise of ionized mass of 2) is called deuterium(2H). A hydrogen atom gas consisting of positive ions and free electrons in with one proton and two neutrons (atomic mass of 3) proportions resulting in a relatively neutral electric is called tritium(3H). Protium and deuterium are stable charge. It's particles are close enough together that isotopes, while tritium is a radioactive isotope. they act collectively when exposed to a magnetic field. Plasma is also electrically conductive. It is sustained STATES OF MATTER easily at the extremely high temperatures present in stars Matter exists in four common states; solids, liquids, and as such is the most common form of matter in the gases and plasma. A state of matter is the physical universe. Matter can change state through the addition condition of a substance. Solids, liquids and gases are or subtraction of energy. This is discussed further in the the primary states of matter of concern for the aviation next Sub-Module. Module 02 - Physics 1.5 CATALYST A catalyst is a substance that causes or accelerates a chemical reaction without itself being affected. A two part epoxy mix is a good example of a catalyst. The main ingredient is the epoxy resin itself. The second ingredient, when mixed with the resin, causes the resin to harden faster and then remains as part of the epoxy resin mix. The opposite of a catalyst is an inhibitor. Inhibitors slow down reactions. 1.6 Module 02 - Physics  QUESTIONS Question: 1-1 Question: 1-3 What is matter and in what four states is it found? What is the different between a compound and a mixture? Question: 1-2 Name two characteristics affected by the number of electrons in the valence shell of an atom. Module 02 - Physics 1.7  ANSWERS Answer: 1-1 Answer: 1-3 Matter is what all things are made of - whatever Chemical bonding properties and conductivity. occupies space, has mass, and is perceptible to the senses in some way. The four states of matter are solids, liquids, gases and plasmas. Answer: 1-2 Compounds are chemically bonded, there is no chemical bond between the substances in a mixture. 1.8 Module 02 - Physics  MECHANICS PART-66 SYLLABUS LEVELS CERTIFICATION CATEGORY ¦ B1 B2 Sub-Module 02 MECHANICS Knowledge Requirements 2.2 - Mechanics 2.2.1 - Statics Forces, moments and couples, representation as vectors; 2 1 Center of gravity; Elements of theory of stress, strain and elasticity: tension, compression, shear and torsion; Nature and properties of solid, fluid and gas; Pressure and buoyancy in liquids (barometers). 2.2.2 - Kinetics Linear movement: uniform motion in a straight line, motion under constant acceleration 2 1 (motion under gravity); Rotational movement: uniform circular motion (centrifugal/centripetal forces); Periodic motion: pendular movement; Simple theory of vibration, harmonics and resonance; Velocity ratio, mechanical advantage and efficiency. 2.2.3 - Dynamics (a) Mass 2 1 Force, inertia, work, power, energy (potential, kinetic and total energy), heat, efficiency; (b) Momentum, conservation of momentum; 2 2 Impulse; Gyroscopic principles; Friction: nature and effects, coefficient of friction (rolling resistance). 2.2.4 - Fluid Dynamics (a) Specific gravity and density; 2 2 (b) Viscosity, fluid resistance, effects of streamlining; 2 1 Effects of compressibility on fluids; Static, dynamic and total pressure: Bernoulli's Theorem, venturi. Module 02 - Physics 2.1 Level 1 Level 2 A familiarization with the principal elements of the subject. A general knowledge of the theoretical and practical aspects of the subject and an ability to apply that knowledge. Objectives: (a) The applicant should be familiar with the basic elements of the Objectives: subject. (a) The applicant should be able to understand the theoretical (b) The applicant should be able to give a simple description of the fundamentals of the subject. whole subject, using common words and examples. (b) The applicant should be able to give a general description of the (c) The applicant should be able to use typical terms. subject using, as appropriate, typical examples. (c) The applicant should be able to use mathematical formula in conjunction with physical laws describing the subject. (d) The applicant should be able to read and understand sketches, drawings and schematics describing the subject. (e) The applicant should be able to apply his knowledge in a practical manner using detailed procedures. STATICS FORCES, MOMENTS AND COUPLES If two equal forces act on the same point of a rigid body Force is the inf luence tending to change the motion but in exact opposite directions, they cancel each other of a body or produce stress in a stationary body. The out. It is as if there are no applied forces. When two magnitude of such an inf luence on a moving body is forces are equal in magnitude and in opposite directions often calculated by multiplying the mass of the body by but are applied to the body parallel to each other, the its acceleration. The effect of force acting on a stationary forces are said to be coupled. As long as the coupled body or structure is stress. There are different types of forces are not applied at the same point, they produce a stress which are discussed below. The forces acting on rotating force upon the body to which they are applied. a stationary body are typically measured in pounds or The resultant movement caused by the coupled forces newtons. When force is applied some distance from is known as torque. A moment is the distance between the point at which the effects of the force are being an applied force and a reference point. But a moment considered, the force measurement includes a distance torque of coupled forces is independent of any particular component such as pound-inches. reference point making it a free vector. A force not only has a certain magnitude but it also has CENTER OF GRAVITY a specific direction. Because of this, forces are frequently The center of gravity (CG) of an aircraft is the balance represented by vectors. This is evident in discussions point for the aircraft. An aircraft suspended from this on aerodynamics (Module 08) and weight and balance point has no tendency to rotate in either a nose-up or (Module 07A). In both of these disciplines, it is possible nose-down attitude. The CG is the point about which to consider forces that impinge on the aircraft around a the weight of an airplane (or any object) is concentrated. central point. In aerodynamics, the point is the center of lift. In weight and balance computations, the point is the An arm is the horizontal distance that a part of the center of gravity. aircraft or a piece of equipment is located from a manufacturer specified reference point called the datum. A vector is represented by an arrow that points in the A moment is the product of a weight (force) multiplied direction the force is applied. The longer the arrow, the by its arm. The moment for a piece of equipment greater the force. Using geometry, vectors representing installed on an aircraft is in fact a torque value, measured forces in different directions can be consolidated into a in inch-pounds (in-lb) or newton-meters. Calculations single vector pointing in a direction that is the resultant are performed using the weight of various components of the directional forces applied. An example of this is and their respective distances to the aircraft datum in given below in the section on speed and velocity. order to ensure that the center of gravity of an aircraft remains unchanged or within an acceptable range. 2.2 Module 02 - Physics Maintenance personnel are required to incorporate center There are five major stresses to which all aircraft are of gravity considerations during routine inspections subjected: (Figure 2-1) as well as when the aircraft is modif ied with new Tension Shear equipment. Flight personnel must also insure the CG Compression Bending remains within safe limits when loading passengers, Torsion baggage and fuel. The procedure for proper weight and balance calculations as they relate to the center of gravity Tension is the stress that resists a force that tends to pull MECHANICS are discussed in Module 07A of this series. something apart. (Figure 2-1A) The engine pulls the aircraft forward, but air resistance tries to hold it back. ELEMENTS OF THEORY OF STRESS The result is tension, which stretches the aircraft. The Whenever an aircraft is in operation, it experiences tensile strength of a material is measured in pounds per something called stress. External forces are applied square inch (psi) and is calculated by dividing the load to the airframe and engine components. Reactionary (in pounds) required to pull the material apart by its force inside the materials of the components counter the cross-sectional area (in square inches). external forces. This internal resistance to deformation is known as stress. A. Tension B. Compression C. Torsional D. Shear Tension Outside of Bend Bent Structural Member Shear Along Imaginary Line (Dotted) Compression Inside of Bend E. Bending (the combination stress) Figure 2-1. The five stresses that may act on an aircraft and its parts. Module 02 - Physics 2.3 Compression is the stress that resists a crushing force. five major stresses that engineers must consider. For (Figure 2-1B) The compressive strength of a material example, cowling, fairings, and similar parts may not is also measured in psi. Compression is the stress that be subject to significant loads requiring a high degree of tends to shorten or squeeze aircraft parts. strength. However, these parts must have streamlined shapes to meet aerodynamic requirements, such as Torsion is the stress that resists twisting. (Figure reducing drag or directing airflow. 2-1C) While moving the aircraft forward, the engine also tends to twist it to one side, but other aircraft STRAIN components hold it on course. Thus, torsion is created. If the stress acting on an object is great enough, it The torsion strength of a material is its resistance to can cause the object to change its shape or to become twisting or torque. distorted. One characteristic of matter is that it tends to be elastic, meaning it can be forced out of shape when a Shear is the stress that resists the force tending to cause force is applied, and then return to its original shape when one layer of a material to slide over an adjacent layer. the force is removed. When an object becomes distorted (Figure 2-1D) Two riveted plates in tension subject the by an applied force, the object is said to be strained. rivets to a shearing force. Usually, the shearing strength of a material is either equal to or less than its tensile or On turbine engine test cells, the thrust of the engine is compressive strength. Aircraft parts, especially screws, typically measured by what are called strain gages. When bolts, and rivets, are often subject to a shearing force. the force (thrust) of the engine is pulling out against the strain gages, the amount of distortion is measured and Bending stress is a combination of compression and then translated into the appropriate thrust reading. tension. The rod in Figure 2-1E has been shortened (compressed) on the inside of the bend and stretched on A def lecting beam style of torque wrench uses the the outside of the bend. strain on the drive end of the wrench and the resulting distortion of the beam to indicate the amount of torque An airplane in flight experiences a bending force on the on a bolt or nut. (Figure 2-3) wing as aerodynamic lift tries to raise the wing. This force of lift actually causes the skin on the top of the wing to compress and the skin on the bottom of the wing to be under tension. When the airplane is on the ground sitting on its landing gear, the force of gravity tries to bend the wing downward, subjecting the bottom of the wing to compression and the top of the wing to tension. (Figure 2-2) During certification testing, an aircraft manufacturer intentionally bends the wing up and down to make sure it can take the stress without failing. Strength or resistance to the external loads imposed during operation may be the principal requirement in certain structures. However, there are numerous other characteristics in addition to designing to control the Wing Top is Under Tension Wing Bottom is Under Compression Figure 2-3. Deflecting beam torque wrench, Figure 2-2. Airplane on the ground, wing under tension and compression. measures strain by distortion. 2.4 Module 02 - Physics NATURE AND PROPERTIES OF one another as a liquid. The same is true when heat energy MATTER is added to water. Water vapor is formed as the motion of the molecules causes more freedom of movement between SOLID molecules. But the water existing as a gas (vapor) is still Matter is said to be solid when it has a definite volume formed from millions of H₂O molecules. and shape. The molecules of a solid are tightly bound to each other. They resist changing shape or volume. Solids The heat energy added or subtracted to a substance MECHANICS may be geometrically or irregularly structured. They are is typically measured by temperature. The higher the incompressible and do not contain enough movement of temperature of a substance, the more energy it contains. the molecules to permit a physical change of shape. Heat always flows from hot to cold. These terms express the relative amount of energy present in two substances. LIQUID They do not measure the absolute amount of heat Liquid matter is characterized by molecules that have present. Without a difference in energy levels, there is no more energy and increased movement. This causes the transfer of energy (heat). molecules to be able f low and not take a rigid shape such as a solid. Liquids take the shape of their container Adding heat to a substance does not always raise its even though the volume of a liquid does not change temperature. When a substance changes state, such significantly. Liquids are said to be incompressible. as when a liquid changes into a vapor, heat energy While liquid molecules are able to slide past each other, is absorbed. This is called latent heat. When a vapor they are still closely packed enough that the application condenses into a liquid, this heat energy is given off. of pressure does little to change the volume. The The temperature of a substance remains constant molecules are also closely bound enough to each other during its change of state. All energy absorbed or given that surface tension is created. Surface tension keeps off, the latent heat, is used for the change process. liquids from complete freedom of expansion. It can Once the change of state is complete, heat added to be observed when a container is filled with a liquid to a substance raises the temperature of the substance. slightly over the brim yet the liquid does not spill over. After a substance changes state into a vapor, the rise in temperature of the vapor caused by the addition of still GAS more heat is called superheat. Matter also exists as a gas. This type of matter contains even more heat energy and movement in its molecules. The temperature at which a substance changes from a The bonding that causes surface tension in a liquid does liquid into a vapor when heat is added is known as its not exist in a gas. A greater space between molecules boiling point. This is the same temperature at which a exists. Gases take the shape of their container but vapor condenses into a liquid when heat is removed. unlike liquids, gases are compressible. When pressure The boiling point of any substance varies directly with is applied, the molecules can be made to exist closer pressure. When pressure on a liquid is increased, its to each other. It is possible to put a gas under so much boiling point increases, and when pressure on a liquid is pressure that is changes to a liquid state. decreased, its boiling point also decreases. For example, water boils at 212 °F at normal atmospheric pressure CHANGES BETWEEN STATES (14.7 psi). When pressure on liquid water is increased Matter can change between the states by adding or to 20 psi, it does not boil at 212 °F. More energy is removing energy. The chemical composition of the required to overcome the increase in pressure. It boils material remains the same during all states of matter at approximately 226.4 °F. The converse is also true. but the energy level causes it to be a solid, liquid, or gas. Water can also boil at a much lower temperature simply For example, water is always H₂O, millions of pairs of by reducing the pressure upon it. With only 10 psi of hydrogen atoms covalently bonded to a single oxygen pressure upon liquid water, it boils at 194 °F. (Figure 2-4) atom loosely held next to each other in a liquid state. When energy is removed and water becomes ice, it is still Vapor pressure is the pressure of the vapor that exists H₂O. However, the motion of the molecules is greatly above a liquid that is in an enclosed container at any reduced and they no longer have the energy to slide past given temperature. The vapor pressure developed by Module 02 - Physics 2.5  20 psi 14.7 psi 10 psi 3 194° F 212° F 226° F Catch Figure 2-4. Boiling point of water changes as pressure changes. 10 lbs. Bucket 0.11 cu' various substances is unique to each substance. A substance that is said to be volatile, develops high 0.11 cu' vapor pressure at standard day temperature (59 °F). This is because the boiling point of the substance is Overflow Can 7 lbs. much lower. The vapor pressure of any substance varies directly with temperature. PRESSURE AND BUOYANCY Figure 2-5. Example of buoyancy. BUOYANCY A solid body submerged in a liquid or a gas weighs less A rchimedes (287–212 B.C.) per formed simi la r than when weighed in free space. This is because of experiments. As a result, he discovered that the buoyant the upward force, called buoyant force, which any fluid force which a f luid exerts upon a submerged body is exerts on a body submerged in it. An object will float if equal to the weight of the fluid the body displaces. This this upward force of the fluid is greater than the weight statement is referred to as Archimedes' principle. This of the object. Objects denser than the fluid, even though principle applies to all fluids, gases as well as liquids. Just they sink readily, appear to lose a part of their weight as water exerts a buoyant force on submerged objects, air when submerged. A person can lift a larger weight under exerts a buoyant force on objects submerged in it. water than he or she can possibly lift in the air. The amount of buoyant force available to an object can The following experiment is illustrated in Figure 2-5. be calculated by using the following formula: The overflow can is filled to the spout with water. The heavy metal cube is first weighed in still air and weighs Buoyant Force = Volume of Object × Density of 10 lb. It is then weighed while completely submerged Fluid Displaced in the water and it weighs 3 lb. The difference between the two weights is the buoyant force of the water. As If the buoyant force is more than the object weighs, the the cube is lowered into the overflow can, the water is object will f loat. If the buoyant force is less than the caught in the catch bucket. The volume of water which object weighs, the object will sink. For the object that overflows equals the volume of the cube. (The volume sinks, its measurable weight will be less by the weight of of irregular shaped objects can be measured by this the displaced fluid. method.) If this experiment is performed carefully, the weight of the water displaced by the metal cube exactly Example: A 10-ft³ object weighing 700 lbs is placed in equals the buoyant force of the water, which the scale pure water. Will the object float? If the object sinks, what shows to be 7 lb. is its measurable weight in the submerged condition? If the object floats, how many cubic feet of its volume is below the water line? 2.6 Module 02 - Physics  Buoyant Force = Volume of Object × Density of Fluid Displaced = 10 (62.4) = 624 lb Because the buoyant force is less than the object weighs, the object will sink. The difference between the buoyant MECHANICS force and the object's weight will be its measurable weight, or 76 lb. Figure 2-6. DeHavilland Twin Otter seaplane. Two good examples of buoyancy are a helium filled airship and a seaplane on floats. An airship is able to float in the atmosphere and a seaplane is able to float on water. Suspension Cables That means both have more buoyant force than weight. Nose Cone Light Sign Neoprene Support Cover Figure 2-6 is a DeHavilland Twin Otter seaplane, with Control Surfaces a gross takeoff weight of 12 500 lb. At a minimum, the f loats on this airplane must be large enough to displace a weight in water equal to the airplane's weight. Certification standards typically require that the floats must be 80 percent larger than the minimum needed to Air Valves Forward support the airplane. Balloonet Aft Balloonet Passenger Car Engines For this airplane, the necessary size of the floats would Air Scoops be calculated as follows. Figure 2-7. Inside view of the Goodyear airship. Divide the airplane weight by the density of water. The ballonets, items 2 and 4 in the picture, are air 12 500 ÷ 62.4 = 200.3 ft³ chambers within the airship. Through the air scoop, air can be pumped into the ballonets or evacuated from the Multiply this volume by 80%. ballonets in order to control the weight of the airship. 200.3 × 80% = 160.2 ft³ Controlling the weight of the airship controls how much positive or negative lift it has. Although the airship is Add the two volumes together to get the total volume classified as a lighter-than-air aircraft, it is in fact flown of the floats. in a condition slightly heavier than air. 200.3 + 160.2 = 360.5 ft³ FLUID PRESSURE By looking at the Twin Otter in Figure 2-6, it is obvious The pressure exerted on the bottom of a container by a that much of the volume of the floats is out of the water. liquid is determined by the height of the liquid and not This is accomplished by making sure the f loats have by the shape of the container. This can be seen in Figure at least 80 percent more volume than the minimum 2-8, where three different shapes and sizes of containers necessary. are full of colored water. Even though they are different shapes and have different volumes of liquid, each one Some of the large Goodyear airships have a volume has a height of 231 inches. Because of this height, each of 230 000 ft³. Since the f luid they are submerged one would exert a pressure on the bottom of 8.34 psi. in is air, to find the buoyant force of the airship, the The container on the left, with a surface area of 1 in², volume of the airship is multiplied by the density of air contains a volume of 231 in³ (one gallon). One gallon of (.076 51 lb⁄ft³). For this Goodyear airship, the buoyant water weighs 8.34 lb, which is why the pressure on the force is 17 597 lb. Figure 2-7 shows an inside view of the bottom is 8.34 psi. Goodyear airship. Module 02 - Physics 2.7 Still thinking about Figure 2-8, if the pressure was forces (gravity and atmospheric pressure) will equalize measured half way down, it would be half of 8.34, or and the mercury will stabilize at a certain height in the 4.17 psi. In other words, the pressure is adjustable by tube. Under standard day atmospheric conditions, the varying the height of the column. Pressure based on the air in a 1 square inch column extending to the top of column height of a fluid is known as static pressure. With the atmosphere weighs 14.7 lb. A 1 square inch column liquids, such as gasoline, it is sometimes referred to as of mercury, 29.92 inches tall, also weighs 14.7 lb. That a head of pressure. For example, if a carburetor needs is why 14.7 psi is equal to 29.92 "Hg when referring to a to have 2 psi supplied to its inlet (head of pressure), barometric reading. Figure 2-9 demonstrates this point. this could be accomplished by having the fuel tank positioned the appropriate number of inches higher than the carburetor. Each container is filled with colored water to a height of 231 inches. As identified in the previous paragraph, pressure due to the height of a fluid column is known as static pressure. 1 in 2 100 in 2 150 in 2 When a fluid is in motion, and its velocity is converted to pressure, that pressure is known as ram. When ram pressure and static pressure are added together, the result is known as total pressure. In the inlet of a gas turbine engine, for example, total pressure is often measured to provide a signal to the fuel metering device or to provide a signal to a gauge on the flight deck. This same principle of pressure caused by a column of fluid applies to the earth's atmosphere. Air is a fluid that has weight. This weight causes atmospheric pressure. On a standard day at sea level, if a 1 square inch column of air extending to the top of the atmosphere is weighed, it would weigh 14.7 lb. That is why standard day Each Pressure Gauge reads 8.34 psi atmospheric pressure is said to be 14.7 pounds per square inch (14.7 psi). Figure 2-8. Fluid pressure based on column height. Since atmospheric pressure at any altitude is due to the weight of air above it, pressure decreases with increased Vacuum altitude. Obviously, the total weight of air above an area at 15 000 ft would be less than the total weight of the air above an area at 10 000 ft. Mercury Atmospheric pressure is often measured by a mercury 14.7 psi 760 mm barometer. A glass tube somewhat over 30 inches in Atmospheric 29.92 in Pressure length is sealed at one end and then filled with mercury. It is then inverted and the open end placed in a dish of mercury. Immediately, the mercury level in the inverted tube will drop a short distance, leaving a small volume of mercury vapor at nearly zero absolute pressure in the tube just above the top of the liquid mercury column. Gravity acting on the mercury in the tube will try to make the mercury run out. Atmospheric pressure pushing down on the mercury in the open container tries to make the mercury stay in the tube. At some point these two Figure 2-9. Atmospheric pressure as inches of mercury. 2.8 Module 02 - Physics A second means of measuring atmospheric pressure is with an aneroid barometer. This mechanical instrument is a much better choice than a mercury barometer for use on airplanes. Aneroid barometers (altimeters) are used to indicate altitude in flight. The pressure of the atmosphere is exerted against an thin metal aneroid connected to the pointer. Calibrations are made in thousands of feet MECHANICS rather than in psi or inches of mercury. For example, the standard pressure at sea level is 29.92 "Hg, or 14.7 psi. At 10 000 feet above sea level, standard pressure is 20.58 "Hg, or 10.10 psi. Altimeters are calibrated so that if the pressure exerted by the atmosphere is 10.10 psi, the altimeter will point to 10 000 ft. (Figure 2-10) Figure 2-10. An airplane's altimeter is an aneroid barometer. KINETICS MOTION Velocity is that quantity in physics which denotes The study of the relationship between the motion of both the speed of an object and the direction in which bodies or objects and the forces acting on them is often the object moves. Velocity can be defined as the rate called the study of "force and motion." In a more specific of motion in a particular direction. Velocity is also sense, the relationship between velocity, acceleration, described as being a vector quantity, a vector being a and distance is known as kinematics. line of specific length, having an arrow on one end or the other. The length of the line indicates the number UNIFORM MOTION value and the arrow indicates the direction in which that Motion may be def ined as a continuing change of number is acting. position or place, or as the process in which a body undergoes displacement. When an object is at different Two velocity vectors, such as one representing the points in space at different times, that object is said to be velocity of an airplane and one representing the velocity in motion, and if the distance the object moves remains of the wind, can be added together in what is called vector the same for a given period of time, the motion may be analysis. Figure 2-11 demonstrates this, with vectors "A" described as uniform. Thus, an object in uniform motion and "B" representing the velocity of the airplane and always has a constant speed. the wind, and vector "C" being the resultant. With no wind, the speed and direction of the airplane would be SPEED AND VELOCITY that shown by vector "A." When accounting for the wind In everyday conversation, speed and velocity are often direction and speed, the airplane ends up flying at the used as if they mean the same thing. In physics they speed and direction shown by vector "C." have definite and distinct meanings. Speed refers to how fast an object is moving, or how far the object will travel Imagine that an airplane is flying in a circular pattern in a specific time. The speed of an object tells nothing at a constant speed. Because of the circular pattern, the about the direction an object is moving. For example, if airplane is constantly changing direction, which means the information is supplied that an airplane leaves New the airplane is constantly changing velocity. The reason York City and travels 8 hours at a speed of 150 mph, this for this is the fact that velocity includes direction. information tells nothing about the direction in which the airplane is moving. At the end of 8 hours, it might To calculate the speed of an object, the distance it be in Kansas City, or if it traveled in a circular route, it travels is divided by the elapsed time. If the distance is could be back in New York City. measured in miles and the time in hours, the units of Module 02 - Physics 2.9  as an acceleration of 2.93 feet per second per second Vector B = Wind (fps/s). By comparison, the acceleration due to gravity is 32.2 fps/s. To calculate acceleration, the following formula is used. Velocity Final (Vf) − Velocity Initial (Vi) Acceleration (A) = Time (t) Vector A = Velocity of Airplane Example: An Air Force F-15 fighter is cruising at 400 mph. The pilot advances the throttles to full afterburner and accelerates to 1 200 mph in 20 seconds. What is the average acceleration in mph/s and fps/s? Vf - Vi A= t 1 200 - 400 A= 20 A = 40 mph ⁄s, or by multiplying by 1.467 A = 58.7 fps ⁄s ne In the example just shown, the acceleration was found to irpla be 58.7 fps/s. Since 32.2 fps/s is equal to the acceleration of A due to gravity, divide the F-15's acceleration by 32.2 to ent ovem find out how many G forces the pilot is experiencing. In =M this case, it would be 1.82 Gs. tor C Vec NEWTON'S LAWS OF MOTION FIRST LAW Objects at rest tend to remain at rest and objects in motion tend to remain in motion at the same speed and in the same Figure 2-11. Vector analysis for airplane velocity and wind velocity. direction, unless acted on by an external force. speed will be miles per hour (mph). If the distance is When a magician snatches a tablecloth from a table measured in feet and the time in seconds, the units of and leaves a full setting of dishes undisturbed, he is not speed will be feet per second (fps). To convert mph to displaying a mystic art; he is demonstrating the principle fps, multiply by 1.467. Velocity is calculated the same of inertia. Inertia is responsible for the discomfort felt way, the only difference being it must be recalculated when an airplane is brought to a sudden halt in the every time the direction changes. parking area and the passengers are thrown forward in their seats. Inertia is a property of matter. This property ACCELERATION of matter is described by Newton's first law of motion. Acceleration is defined as the rate of change of velocity. If the velocity of an object is increased from 20 mph to SECOND LAW 30 mph, the object has been accelerated. If the increase When a force acts upon a body, the momentum of that body is in velocity is 10 mph in 5 seconds, the rate of change in changed. The rate of change of momentum is proportional to velocity is 10 mph in 5 seconds, or 2 mph per second. If the applied force. this were multiplied by 1.467, it could also be expressed 2.10 Module 02 - Physics Bodies in motion have the property called momentum. When an aircraft propeller pushes a stream of air A body that has great momentum has a strong tendency backward with a force of 500 lbs, the air pushes the to remain in motion and is therefore hard to stop. For blades forward with a force of 500 lbs. This forward force example, a train moving at even low velocity is difficult causes the aircraft to move forward. A turbofan engine to stop because of its large mass. Newton's second law exerts a force on the air entering the inlet duct, causing applies to this property. Based on Newton's second law, it to accelerate out the fan duct and the tailpipe. The air the formula for calculating thrust is derived, which accelerating to the rear is the action, and the force inside MECHANICS states that force equals mass times acceleration (F = the engine that makes it happen is the reaction, also MA). Earlier in this chapter, it was determined that called thrust. mass equals weight divided by gravity, and acceleration equals velocity final minus velocity initial divided by CIRCULAR MOTION time. Putting all these concepts together, the formula Circular motion is the motion of an object along a curved for thrust is: path that has a constant radius. For example, if one end of a string is tied to an object and the other end is held in Weight (Velocity final − Velocity initial) Force = the hand, the object can be swung in a circle. The object Gravity (Time) is constantly deflected from a straight (linear) path by W (Vf − Vi) the pull exerted on the string, as shown in Figure 2-12. F= Gt When the weight is at point A, due to inertia it wants to keep moving in a straight line and end up at point Example: A turbojet engine is moving 150 lb of air per B. Because of the force being exerted on the string, it is second through the engine. The air enters going 100 forced to move in a circular path and end up at point C. fps and leaves going 1 200 fps. How much thrust, in pounds, is the engine creating? The string exerts a centripetal force on the object, and the object exerts an equal but opposite force on the string, W (Vf − Vi) obeying Newton's third law of motion. The force that F= Gt is equal to centripetal force, but acting in an opposite 150 (1 200 − 100) direction, is called centrifugal force. Centripetal force is F= 32.2 (1) always directly proportional to the mass of the object in circular motion. Thus, if the mass of the object in Figure F = 5 124 lb of thrust 2-12 is doubled, the pull on the string must be doubled to keep the object in its circular path, provided the speed THIRD LAW of the object remains constant. For every action there is an equal and opposite reaction. Centripetal force is inversely proportional to the radius Newton's third law of motion is often called the law of of the circle in which an object travels. If the string in action and reaction. This means that if a force is applied Figure 2-12 is shortened and the speed remains constant, to an object, the object will