# Strain

Strain, abbreviated as \(\epsilon\) (Greek symbol epsilon), also called linear strain or longitudinal strain, is the deformation, stretched or compressed, of a material compared to its original length.

### Strain formula

\(\large{ \epsilon = \frac{ \Delta l }{ l_i } }\)

\(\large{ \epsilon = \frac { \sigma } { E } }\)

Where:

\(\large{ \epsilon }\) (Greek symbol epsilon) = strain

\(\large{ \Delta l }\) = length differential

\(\large{ l_i }\) = initial length

\(\large{ \sigma }\) (Greek symbol sigma) = stress

\(\large{ E }\) = Young's modulus