Strength of Materials

3.1 DEFINITIONS

External forces acting on a body do certain work causing deformation at their points of application. This means that there is a certain work done to strain the body from its undeformed state. As per the first law of thermodynamics, the work done on a body by the external forces in a certain time interval is equal to the change in the internal energy.

Strain energy is the energy which is stored in the body due to the effect of straining. Perfect elastic bodies show the same amount of work done during the loading and unloading process. Thus, all the work done during the elastic deformation is stored and is recovered at the release of loads.

Elastic strain energy is the recoverable stored energy in an elastic body.

Resilience is ...