Elongation of a bar due to its Own weight

Analysis of a hanging beam:

A BAR HANGING

LONGITUDINAL STRAIN AND LATERAL STRAIN

STRAIN

When a body is subjected to an axial load, there is increase in length in one direction at the same time the dimensions decrease in perpendicular directions.

                     Hence, the ratio of change in dimension to original dimension is known as "STRAIN"

Forces on a body showing strain.

Elastic Modulii

Types of Elastic Modulii

                      There are two types of elastic modulus based on the nature of the stresses:

    1)Modulus of Elasticity ( compressive or tensile stress )

    2)Modulus of Rigidity   ( Shear stress )

Hooke's Law

Hooke's Law 

Hooke's law states that,

             

ELASTICITY AND ELASTIC LIMIT.

Elasticity

        " When a body is subjected to an external force, the body tends to undergo some deflection. When the external force is removed, the body regains it's original position. Such a body is said to be 'ELASTIC BODY'. This property, by which the material regains it's original position is called 'ELASTICITY'. "

Stress and Types of Stresses.

Stress:

"When a body is subjected to some external force, there is some resistive force generated per unit area, This resistive force generated per unit area is known as 'Stress'."