The new international system of units (SI) is used through­ out the text. However, taking into account that the engi­neers’ system (mkgfs) still finds wide use, the units of this system are also given. Moreover, wherever necessary the rela­ tions are indicated between the units of the international and engineers’ systems. Normative and design data are given in both systems of units.In the presentation of the material primary emphasis is placed on the practical significance of conclusions.To gain a better understanding of theoretical propositions, the solutions of sample problems are given. All solutions are first carried out in algebraic form and then numerical data are substituted.Although the book is mainly intended for full-time vocatio­nal schools, the large number of detailed and specially selec­ted examples makes it handy for their evening and correspon­dence departments as well.Translated from the Russian by M. KonyaevaFrom the Authors 5Notation 12Introduction 15Chapter I. Basic Definitions and Axioms of Statics 17 1. Fundamentals 17 2. Axioms of Statics 22 3. Constraints and Their Reactions. Axioms of Constraints 25 Chapter II. Systems of Concurrent Forces in a Plane 28 4. Analytic Determination of the Resultant of Two Forces Applied at the Same Point 28 5. Resolution of a Force into Two Components Ap­plied at the Same Point 30 6. Point Addition of Concurrent Forces in a Plane. Force Polygon 32 7. Projection of a Force on an Axis 338. Projection of a Vector Sumon an Axis 369. Analytic Determination of the Resultant of a Sys­tem of Concurrent Forces (Method of Projections)  37 10. Conditions and Equations of Equilibrium for a Sys­tem of Concurrent Forces 39 11. Procedure for Solving Equilibrium Problems 40 12. Theorem of Concurrence of Three Mutually Balanced Non-Parallel Forces 49Chapter III. Couple 5213. Addition of Two Parallel Forces of the Same Sense 52 14. Addition of Two Parallel Forces of OppositeSense 53 15. Moment of a Couple 56 16. Equivalence of Couples. Translation of a Couple in Its Plane of Action 58 17. Theorem of Equivalent Couples 60 18. Addition of Couples Acting in the Same Plane 61Chapter IV. Two-Dimensional Systems of Arbitrarily Located Forces 6519. Moment of a Force About a Point 65 20. Equilibrium of a Lever 67 21. Reduction of a Force to a Given Point 69 22. Reduction of a Two-Dimensional Force System to a Given Point 70 23. Resultant of a Two-Dimensional Force System 72 24. Theorem of the Moment of a Resultant (Varignon’s Theorem) 73 25. A Case of the Reduction of a Two-Dimensional Force System to a Couple 79  26. Conditions and Equations of Equilibrium for a Two-Dimensional Force System 80  27. Three Forms of Equilibrium Equations 8228. Supporting Devices of Beam Systems 85 29. Classification of Loads 88 30. Practical Solution of Equilibrium Problems for Two-Dimensional Force Systems 89 31. Equilibrium of a System of Connected Bodies 101Chapter V. Friction 10632. Types of Friction 106 33. The Laws of Sliding Friction 107 34. Angle and Cone of Friction 109 35. Experimental Determination of Coefficients of Friction 11436. The Laws of Rolling Friction 116  Chapter VI. Three-Dimensional Force Systems 12037. Force Parallelepiped 12038. Equilibrium of a System of Concurrent Forces in Space 12139. Moment of a Force About an Axis 12340. Equilibrium of an Arbitrary Three-Dimensional Force System 128Chapter VII Centroids and Centres of Gravity 13441. Centre of Parallel Forces 13442. Co-ordinates of the Centre of ParallelForces 13543. Centroid of a Volume 13944. Centroid of an Area. Static Moments of an Area 14145. Centroid of a Line 14746. Stability of Equilibrium 147PART 2. KINEMATICSChapter VIII. Fundamentals 15447. Subject of Kinematics 15448. Space and Time 15449. Basic Definitions 156Chapter IX. Kinematics of Particles 16050. Methods of Specifying the Motion of a Particle 160 51. Velocity of a Particle 162 52. Acceleration of a Particle 167 53. Types of Motion of a Particle as Related to Acce­leration 174 54. Uniformly Variable Motion of a Particle 176 55. Kinematic Graphs and Relationship Between Them 180Chapter X. Simple Motions of Rigid Bodies 18556. Translation of a Rigid Body 18557. Rotation of a Rigid Body About a Fixed Axis 18658. Velocities and Accelerations of Points of a Rotating Body 191 Chapter XI. Methods of Transmission of Rotary Motion 19859. Classification of Transmission Mechanisms 198 60. Gear Ratio 198 61. Cylinder Friction Drives 200 62. Face Friction Drives 20263. Cone Friction Drives 203 64. Belt Drives: Fundamental Concepts 205 65. Gear Drives: General Considerations 206 66. Gear Ratio of a Spur Gear Drive 20767. Gear Trains 20868. Worm Gearing 212Chapter XII Complex Motion of Particles 21669. Base, Relative and Absolute Motions 216 70. Theorems on Addition of the Velocities and Accelerations of a Particle in Complex Motion 219Chapter XIII. Plane Motion. 22571. Concept of Plane Motion of a Rigid Body 22572. Determination of the Velocity of Any Point of a Body in Plane Motion 22673. Instantaneous Centre of Zero Velocity 22874. Determination of the Acceleration of Any Point of a Body in Plane Motion 24075. Planetary Gearing 24476. Differential Gearing 247 PART 3. DYNAMICSChapter XIV Basic Concepts and Axioms of Dynamics 25177. Subject of Dynamics 251 78. Principle of Inertia 25279. Fundamental Law of Dynamics of Particles 252 80. Systems of Units 254 81. Axiom of Superposition 256 82. Axiom of Interaction 258 83. Two Basic Problems of Dynamics 259Chapter XV. Motion of Particles. Method of Kinetostatics 26884. Ideal and Real Constraints 268 85. D ’Alembert’s Principle 269 86. Inertia Force for a Particlein Rectilinear Motion 271  87. Inertia Force for a Particle in Curvilinear Motion 27188. Inertia Force for a Rigid Body 27489. Solution of Problems by the Method of Kineto­statics 275Chapter XVI Work and Power 28090. Work of a Constant Force in Rectilinear Motion 280 91. Work of a Variable Force in Curvilinear Motion 282 92. Work of a Resultant Force 283 93. Work of a Force of Gravity 285 94. Work of an Elastic Force 28695. Concept of Mechanical Efficiency 28996. Efficiency of a System of Mechanisms Connected in Series 290 97. Efficiency of a System of Mechanisms Connected in Parallel 29198. Power 29699. Work and Efficiency for Bodies Sliding Along an Inclined Plane 298100. Work and Power in Rotation 306101. Work in Rolling Motion 308Chapter XVII The Laws of Dynamics 315102. Concept of a System of Particles 315 103. Law of Momentum for a Particle 317 104. Law of Momentum for a System of Particles 322 105. Potential and Kinetic Energy 324 106. Kinetic Energy of a Body in Various Types of Motion 325 107. Moments of Inertia of Homogeneous Bodies of Simple Shape 327 108. Law of Kinetic Energy for a Particle 330 109. Law of Kinetic Energy for a System of Particles 333 110. Fundamental Equation of Dynamics for a Rigid Body in Rotation 338Chapter XVIII. Application of the Laws of Kinematics and Dynamics to the Analysis to Mechanisms 345111. Principles and Definitions 345 112. Fundamentals of Kinematics of Mechanisms 350113. Examples of Constructing Velocity Diagrams 359114. Distribution of Accelerations in a Body in Plane Motion 363115. Examples of Constructing Acceleration Diagrams 367116. Cam Gears 374117. Introduction to the Dynamics of Machinery 381118. Fundamentals of the Dynamic Analysis of Mecha­nisms 387119. Fundamentals of Regulation. 395Subject Index 406