Difficulty: Easy
Correct Answer: Modulus of elasticity
Explanation:
Introduction / Context:Stress–strain relationships describe how materials deform under load. Within the elastic range, deformation is reversible and a proportionality exists between stress and strain. The constant of proportionality for normal (tensile/compressive) loading defines a fundamental material property used in structural and pressure equipment design.
Given Data / Assumptions:
Concept / Approach:Young’s modulus (modulus of elasticity, E) is defined as E = σ/ε for linear elastic behavior in tension or compression. Other moduli describe different loading modes: modulus of rigidity (G) relates shear stress to shear strain, while bulk modulus (K) relates volumetric stress to volumetric strain (hydrostatic loading).
Step-by-Step Solution:
Identify loading mode: normal stress and normal strain.Apply Hooke’s law for uniaxial elasticity: σ = E * ε.Therefore, the ratio σ/ε equals the modulus of elasticity (Young’s modulus).Verification / Alternative check:Interrelations E, G, and K exist for isotropic materials: E = 2G(1 + ν) and E = 3K(1 − 2ν), where ν is Poisson’s ratio, confirming distinct meanings of each modulus.
Why Other Options Are Wrong:
Common Pitfalls:Confusing G and E; using tangent or secant moduli outside the strictly linear region; ignoring temperature dependence of elastic properties.
Final Answer:Modulus of elasticity
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