Stress and Strain Understand the fundamentals of how materials deform under different types of loads. This section covers tensile, compressive, and shear stresses, along with strain, modulus of elasticity, and Poisson’s ratio. 1 / 20 The ability of a material to withstand load without permanent deformation is Elasticity Plasticity Toughness Malleability Elastic materials return to their original shape once the load is removed. 2 / 20 A material is said to be perfectly elastic when It regains its original shape completely after unloading It deforms permanently after unloading It absorbs maximum energy It fractures instantly Perfect elasticity means no permanent deformation. 3 / 20 If the stress is directly proportional to strain, the material obeys Pascal’s Law Newton’s Law Bernoulli’s Law Hooke’s Law Hooke’s Law: Stress ∝ Strain within elastic limit. 4 / 20 When equal forces act tangentially to the opposite faces of a cube, the stress developed is Compressive Stress Bearing Stress Shear Stress Tensile Stress Tangential forces produce shear stress. 5 / 20 The slope of the stress–strain curve within the elastic limit gives Shear Modulus Young’s Modulus Bulk Modulus Rigidity Modulus E = Stress / Strain in the linear (elastic) region. 6 / 20 The stress induced when a body is subjected to equal and opposite forces along its length is Tensile Stress Shear Stress Compressive Stress Bearing Stress Tensile stress tries to elongate the material. 7 / 20 The property that defines resistance to deformation is Plasticity Brittleness Elasticity Toughness Elastic materials regain original shape after deformation. 8 / 20 The working stress is always Independent of it Less than ultimate stress Equal to yield stress Greater than yield stress Working stress ensures a safety margin below ultimate stress 9 / 20 The stress acting on an inclined plane due to an axial load is Bending Stress Normal Stress Shear Stress Bearing Stress Axial load acts perpendicular to cross-section, causing normal stress. 10 / 20 The ability of a material to absorb energy within elastic limit is called Resilience Toughness Ductility Brittleness Resilience = energy stored per unit volume within elastic range. 11 / 20 The energy stored per unit volume under elastic deformation is called Elastic Work Resilience Impact Energy Impact Energy Strain Energy Strain energy = ½ × Stress × Strain. 12 / 20 The ratio of lateral strain to longitudinal strain is Modulus of Rigidity Elastic Constant Poisson’s Ratio Flexural Modulus μ = Lateral Strain / Longitudinal Strain. 13 / 20 The stress corresponding to permanent deformation is called Proof Stress Yield Stress Working Stress Breaking Stress Yield stress indicates the onset of plastic behavior. 14 / 20 Within the elastic limit, the ratio of stress to strain is Modulus of Elasticity Bulk Modulus Shear Modulus Plastic Constant E = Stress / Strain; it measures stiffness of a material. 15 / 20 The maximum stress a material can resist before failure is Working Stress Breaking Stress Fatigue Stress Ultimate Stress Ultimate stress represents maximum strength before fracture. 16 / 20 In a stress–strain curve, the point beyond which material deforms permanently is Proportional Limit Yield Point Elastic Limit Breaking Point Beyond the yield point, material experiences plastic deformation 17 / 20 Hooke’s law is valid only within the Yield limit Plastic limit Ultimate limit Elastic limit Hooke’s law applies while material obeys linear stress–strain relation. 18 / 20 The unit of stress in the SI system is kg/m³ Pascal N/m Joule 1 Pascal = 1 N/m². 19 / 20 The ratio of change in length to the original length is known as Stress Strain Toughness Rigidity Strain = ΔL / L; it is dimensionless. 20 / 20 The ratio of force to the area over which it acts is called Stress Strain Modulus Pressure Stress = Force / Area; it defines internal resistance to deformation Your score isThe average score is 51% 0% Restart quiz