CHAPTER 6 : ELASTICITY
6.1 Definition of Elasticity
When externally applied forces are balanced, no net force will
act on the object and hence no translational motion can be produced. However,
deformation in shape or/and size can occur depending on the intermolecular forces
with which the molecules or atoms of the subject hold each other. In such a
case the objects can be classified as follows :
Rigid Objects
If no deformation occurs whatsoever, then the object is called a Rigid Object.
Elastic Objects
Deformation does occur, but it disappears if the balanced external forces are
removed.
Plastic Objects
Here, deformation does occur, and it remains permanent even if the balanced
external forces are removed.
From the above classification the elastic property can be defined as :
If the object is capable of resisting deformation and is capable
of overcoming deformation and regaining its original shape and size when externally
applied balanced forces are removed then the object possesses the property called
elasticity.
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