Q1: Presence of nickel & chromium in steel does not raise its

ANS:A - elastic limit

The elastic limit, also known as the proportional limit, is a fundamental concept in materials science and mechanics, particularly in the study of the behavior of materials under mechanical loading. The elastic limit refers to the maximum stress that a material can withstand without undergoing permanent deformation after the load is removed. In other words, it is the point at which a material transitions from elastic deformation to plastic deformation. When a material is subjected to an external force, it deforms elastically up to a certain point, known as the elastic limit. During elastic deformation, the material exhibits a linear stress-strain relationship, meaning that the amount of deformation (strain) is directly proportional to the applied stress. This behavior follows Hooke's Law, which states that the stress is proportional to the strain within the elastic limit. Once the stress exceeds the elastic limit, the material begins to deform plastically, meaning that it undergoes permanent deformation even after the load is removed. Plastic deformation involves the rearrangement of atomic or molecular bonds within the material's structure, resulting in changes in shape or size that are not reversible. The elastic limit is an important parameter for characterizing the mechanical behavior of materials, as it provides information about their ability to withstand loading without undergoing permanent damage. Materials with higher elastic limits are generally considered more resilient and suitable for applications where dimensional stability and resistance to deformation are important. It's worth noting that the elastic limit is often difficult to precisely determine experimentally, especially for materials that exhibit complex behavior such as nonlinearity, strain hardening, and hysteresis. In practice, engineers often use the proportional limit or yield strength as practical indicators of the elastic limit in engineering applications.