Question

1.1 The difference between elastic and plastic (inelastic) behavior of materials is

a. With elastic behavior, prediction of material behavior is possible; with plastic, it is not.

b. With plastic behavior, prediction of material behavior is possible; with elastic, it is not.

c. The different type of design standards based on type of material

d. There is no difference

Also, the units of deformation are in what?

		Inches/inch
		Psi/in
		Inches2
		Inches3

Answer 1

answer c is correct .

The terms ‘plastic’ and ‘elastic’ are, physical properties, used to describe an object. Elasticity is a property of a material to be flexible or buoyant in nature. When an external force is applied to a body, the body falls apart.This happens because the distance between the lattice atoms increases and each atom tries to pull its neighbor closer to itself. The ‘elastic limit’ of a body is defined as the maximum extent to which a solid may be stretched with out permanent deformation.

Plasticity is defined as the ability of a body to change its shape and size permanently, when an external force is applied. In a plastic body, when a force is applied, from the many layers of atoms, two of these layers slide from their crystal planes, and loose their elastic limit, which causes the deformation in the body.

so based on the typw of material, different design standards are implemented.

deformation means change of shape divided by its original shape. i.e. in case of length it will be change in length divided by its original length. so it is dimensionless so option A is correct .