Unit 1 : Introduction to Engineering Mechanics Force and characteristics of a force, Force system : Definition, Classification of force system according to plane and line of action, Composition of forces : Definition, Resultant force, Moment of a force, Principle of transmissibility of forces, Law of moments, Simple problems on forces. (Chapter - 1) Unit II : Simple Stresses and Strains Definition of rigid body, Plastic body, Mechanical properties of metal - (Rigidity, Elasticity, Plasticity, Compressibility, Hardness, Toughness, Stiffness, Brittleness, Ductility, Malleability, Creep, Fatigue, Tenacity, Durability), Definition of stress, Strain, Classification of stress, Strain, (Types of stresses-Tensile, Compressive and shear stresses types of strains - Tensile, Compressive and shear strains - Elongation and contraction - Longitudinal and lateral strains - Poisson's ratio) Stress-strain curve for mild steel, HYSD bar and non-ferrous materials, (Yield stress/proof stress, Hooke's law, St. Venant's principle, Ultimate stress, Breaking stress and percentage elongation. Working stress - Factor of safety - Percentage reduction in area - Significance of percentage elongation and reduction in area of cross section), Stresses in bars of composite section (Modular ratio - Problems on axially loaded composite sections like R.C.C / Encased columns) Principles of superposition, Deformation of uniform bars and bars of varying cross-section, Volumetric strain and change in volume, Relation among elastic constants. Types of loading - Gradual, Suddenly applied load and impact load, Definition of strain energy, Modulus of resilience.
