What is the formula for calculating strain in a material?

The formula for calculating strain is defined as the ratio of the change in length (extension) of a material to its original length. This relationship is fundamental in understanding how materials deform under stress. Strain provides a measure of the deformation experienced by the material relative to its original length, which is crucial in engineering to assess material behavior under applied loads.

Strain is expressed mathematically as:

Strain = (Change in Length) / (Original Length)

In this context, "extension" refers to the increase in length that the material undergoes when subjected to a tensile load. Therefore, the correct formula highlights that strain is directly related to how much the original length has changed.

This understanding of strain is essential in various engineering applications, such as in the design and analysis of structures, where knowing how materials will deform is critical for safety and performance.