# Poisson's Ratio

Poisson's ratio, abbreviated as Po, \(\mu\) or \(\nu\), is the elastic ratio between lateral strain and longitudinal strain. Poisson's ratio can be considered to be unit-less.

## Formulas that use Poisson's Ratio

\(\large{ \mu = \frac { \varepsilon_t } { \varepsilon_a } }\) |

### Where:

\(\large{ \mu }\) (Greek symbol mu) = Poisson's Ratio

\(\large{ \epsilon_a }\) (Greek symbol epsilon) = axial or longitudinal strain (right angle to load)

\(\large{ \epsilon_t }\) (Greek symbol epsilon) = lateral or transverse strain (direction of load)