Stress vs strain curve represents __________.

Concept:

According to Hooke’s experiment, the relation between the stress and the strain for a given material under tensile stress can be found experimentally.

If we plot a graph of stress vs strain for any metal body, we can see an ideal curve as shown below

This shows that as stress increases strain on material will also increase, but after certain point the curve becomes non-uniform and (i.e., between point A and E).

hence the region between A to B stress and strain are not proportional. The point B in the curve is known as yield point (also known as elastic limit) and the corresponding stress is known as yield strength (σ_y) of the material. below this point the body can retain its original shape and size but if yield stress goes beyond (σ_y) the body will start deforming permanently and is said to be permanently set

And based on this Hooke’s law was given, which states within the elastic limit the stress developed in a body will be directly proportional to the change produced in the body.

i.e., stress ∝ strain

∴ stress = k × Strain

Here k is proportionality constant which is known as modulus of elasticity

Whereas Hooke’s Law is only valid up to yield point, and modulus of elasticity is slope of stress vs strain curve.

Based on this there are three types of modulus of elasticity

Explanation:

From the above explanation we can see that stress vs strain curve represents the stress caused because of strain.

i.e., it represents the relationship between stress and strain

Hence option 1 is correct among all.