Why the relationship for conventionalstrain is valid only for small strains but the relationship for true strain is valid for all strains

Answer:
Engineering strain [i.e. conventional strain](or simply strain, e) is given by change in length
divided by original length. Engineering strain actually indicates an average change in length in a
particular direction. According to definition, s and e are given as





where P is the load applied over area A, and as a consequence of it material attains the final
length L from its original length of L0. Because material dimensions changes under application
of the load continuously, engineering stress and strain values are not the true indication of
material deformation characteristics. Thus the need for measures of stress and strain based on...