Table of Contents

Preface xii
List of Symbols xviii
Introduction 1
What Is Mechanics? 2
Fundamental Concepts and Principles 2
Systems of Units 5
Conversion from One System of Units to Another 10
Method of Problem Solution 11
Numerical Accuracy 13
Statics of Particles 15
Introduction 16
Forces in a Plane 16
Force on a Particle: Resultant of Two Forces 16
Vectors 17
Addition of Vectors 18
Resultant of Several Concurrent Forces 20
Resolution of a Force into Components 21
Rectangular Components of a Force. Unit Vectors 27
Addition of Forces by Summing x and y Components 30
Equilibrium of a Particle 35
Newton's First Law of Motion 36
Problems Involving the Equilibrium of a Particle. Free-Body Diagrams 36
Forces in Space 45
Rectangular Components of a Force in Space 45
Force Defined by Its Magnitude and Two Points on Its Line of Action 48
Addition of Concurrent Forces in Space 49
Equilibrium ofa Particle in Space 57
Review and Summary for Chapter 2 64
Review Problems 67
Computer Problems 69
Rigid Bodies: Equivalent Systems of Forces 73
Introduction 74
External and Internal Forces 74
Principle of Transmissibility. Equivalent Forces 75
Vector Product of Two Vectors 77
Vector Products Expressed in Terms of Rectangular Components 79
Moment of a Force about a Point 81
Varignon's Theorem 83
Rectangular Components of the Moment of a Force 83
Scalar Product of Two Vectors 93
Mixed Triple Product of Three Vectors 95
Moment of a Force about a Given Axis 97
Moment of a Couple 107
Equivalent Couples 108
Addition of Couples 110
Couples Can Be Represented by Vectors 110
Resolution of a Given Force Into a Force at O and a Couple 111
Reduction of a System of Forces to One Force and One Couple 122
Equivalent Systems of Forces 123
Equipollent Systems of Vectors 124
Further Reduction of a System of Forces 124
Reduction of a System of Forces to a Wrench 127
Review and Summary for Chapter 3 146
Review Problems 151
Computer Problems 153
Equilibrium of Rigid Bodies 157
Introduction 158
Free-Body Diagram 159
Equilibrium in Two Dimensions 160
Reactions at Supports and Connections for a Two-Dimensional Structure 160
Equilibrium of a Rigid Body in Two Dimensions 162
Statically Indeterminate Reactions: Partial Constraints 164
Equilibrium of a Two-Force Body 183
Equilibrium of a Three-Force Body 184
Equilibrium in Three Dimensions 191
Equilibrium of a Rigid Body in Three Dimensions 191
Reactions at Supports and Connections for a Three-Dimensional Structure 191
Review and Summary for Chapter 4 211
Review Problems 213
Computer Problems 215
Distributed Forces: Centroids and Centers of Gravity 219
Introduction 220
Areas and Lines 220
Center of Gravity of a Two-Dimensional Body 220
Centroids of Areas and Lines 222
First Moments of Areas and Lines 223
Composite Plates and Wires 226
Determination of Centroids by Integration 236
Theorems of Pappus-Guldinus 238
Distributed Loads on Beams 248
Forces on Submerged Surfaces 249
Volumes 259
Center of Gravity of a Three-Dimensional Body: Centroid of a Volume 259
Composite Bodies 262
Determination of Centroids of Volumes by Integration 262
Review and Summary for Chapter 5 274
Review of Problems 278
Computer Problems 281
Analysis of Structures 284
Introduction 285
Trusses 286
Definition of a Truss 286
Simple Trusses 288
Analysis of Trusses by the Method of Joints 289
Joints under Special Loading Conditions 291
Space Trusses 293
Analysis of Trusses by the Method of Sections 303
Trusses Made of Several Simple Trusses 304
Frames and Machines 315
Structures Containing Multiforce Members 315
Analysis of a Frame 315
Frames Which Cease to Be Rigid When Detached from Their Supports 316
Machines 331
Review and Summary for Chapter 6 343
Review Problems 346
Computer Problems 349
Forces in Beams and Cables 353
Introduction 354
Internal Forces in Members 354
Beams 361
Various Types of Loading and Support 361
Shear and Bending Moment in a Beam 362
Shear and Bending-Moment Diagrams 364
Relations among Load, Shear, and Bending Moment 372
Cables 383
Cables with Concentrated Loads 383
Cables with Distributed Loads 384
Parabolic Cable 385
Catenary 394
Review and Summary for Chapter 7 402
Review Problems 405
Computer Problems 408
Friction 411
Introduction 412
The Laws of Dry Friction. Coefficients of Friction 412
Angles of Friction 415
Problems Involving Dry Friction 416
Wedges 431
Square-Threaded Screws 431
Journal Bearings: Axle Friction 440
Thrust Bearings: Disk Friction 442
Wheel Friction: Rolling Resistance 443
Belt Friction 450
Review and Summary for Chapter 8 461
Review Problems 464
Computer Problems 467
Distributed Forces: Moments of Inertia 471
Introduction 472
Moments of Inertia of Areas 473
Second Moment, or Moment of Inertia, of an Area 473
Determination of the Moment of Inertia of an Area by Integration 474
Polar Moment of Inertia 475
Radius of Gyration of an Area 476
Parallel-Axis Theorem 483
Moments of Inertia of Composite Areas 484
Product of Inertia 497
Principal Axes and Principal Moments of Inertia 498
Mohr's Circle for Moments and Products of Inertia 506
Moments of Inertia of Masses 512
Moment of Inertia of a Mass 512
Parallel-Axis Theorem 514
Moments of Inertia of Thin Plates 515
Determination of the Moment of Inertia of a Three-Dimensional Body by Integration 516
Moments of Inertia of Composite Bodies 516
Moment of Inertia of a Body with Respect to an Arbitrary Axis through O: Mass Products of Inertia 531
Ellipsoid of Inertia: Principal Axes of Inertia 532
Determination of the Principal Axes and Principal Moments of Inertia of a Body of Arbitrary Shape 534
Review and Summary for Chapter 9 545
Review Problems 551
Computer Problems 554
Method of Virtual Work 557
Introduction 558
Work of a Force 558
Principle of Virtual Work 561
Applications of the Principle of Virtual Work 562
Real Machines: Mechanical Efficiency 564
Work of a Force during a Finite Displacement 578
Potential Energy 580
Potential Energy and Equilibrium 581
Stability of Equilibrium 582
Review and Summary for Chapter 10 592
Review Problems 595
Computer Problems 597
Fundamentals of Engineering Examination 601
Photo Credits 603
Index 605
Answers to Problems 611