What is the best definition of elasticity?
Elasticity:
Young's modulus of elasticity:
Within the elastic limit, the ratio of longitudinal stress and longitudinal strain is called Young’s modulus of elasticity .
Bulk modulus of elasticity:
Within the elastic limit, the ratio of the volume stress and the volume strain is called the bulk modulus of elasticity .
Modulus of rigidity:
Within elastic limit, the ratio of shearing stress (or) tangential stress and shearing strain (or) tangential strain is called the modulus of rigidity .