How is the tensile strength of a metal best defined?

The tensile strength of a metal is best defined as the maximum stress that a material can withstand while being stretched or pulled before it experiences fracture. This characteristic is critical for understanding how materials behave under tensile loads and is a key parameter in materials science and structural engineering.

In practical terms, when a metal is subjected to increasing tensile stress, it will initially deform elastically, following Hooke’s Law until it reaches a point of yield. Beyond this yield point, the material undergoes plastic deformation, but it continues to withstand increasing stress until it reaches its ultimate tensile strength—the highest point on the stress-strain curve. Once this maximum stress level is reached, any further increase in load will cause the material to fracture.

The other choices present aspects of material behavior but do not encapsulate the definition of tensile strength. While the stress needed for plastic deformation indicates a transition in material behavior, it does not define the top threshold just before fracture. Likewise, the amount of deformation at the yield point pertains to the elastic and plastic regions of the stress-strain curve and not to the maximum stress. Lastly, the proportion of elongation before breaking refers to ductility rather than tensile strength itself. Understanding tensile strength as the maximum stress before fracture occurs is crucial for assessing material