# Torsion Constant for Square Cross-section

## Torsion Constant for Square Cross-section formula

\(\large{ J = 2.25 \; a^4 }\) |

### Where:

Units |
English |
Metric |

\(\large{ J }\) (Greek symbol alpha) = torsion constant | \(\large{\frac{lbf-ft}{rad}}\) | \(\large{\frac{N-m}{rad}}\) |

\(\large{ a }\) = half the edge length of a square | \(\large{in}\) | \(\large{m}\) |

Tags: Strain and Stress Equations Constant Equations Torsion Constant Equations