Simple Stress and Strain MCQ with answer and solution

Concept

Elastic constants in strength of materials

Formula

NONE

Step-by-step solution

1. Elastic constants relate stress to strain within the elastic limit of an isotropic material. 2. Examples include Young's modulus, Poisson's ratio, Shear modulus, and Bulk modulus. 3. Yield strength measures the limit of elastic behavior and transition to plastic deformation, so it is not an elastic constant. Answer: D

Explanation

Young's modulus, Poisson's ratio, and Shear modulus are elastic constants that define the proportional stress-strain relationship of a material under elastic loading. Yield strength represents the stress threshold where permanent plastic deformation begins rather than an elastic constant. Thus, option D is the correct answer.

Why the other options are wrong

A) Young's modulus is an elastic constant representing the ratio of tensile stress to strain. B) Poisson's ratio is an elastic constant representing the ratio of lateral to longitudinal strain. C) Shear modulus is an elastic constant representing the ratio of shear stress to shear strain.

Shortcut

Elastic constants are E, G, K, and Poisson's ratio; Yield strength is a stress limit, not an elastic constant.

Common mistake

Confusing material strength limits like yield strength with elastic moduli and constants that govern reversible elastic deformation.