Torsional Constant of a Circle formulas |
||
|
\( J \;=\; \dfrac{ \pi \cdot r^4 }{ 2 }\) \( J \;=\; \dfrac{ \pi \cdot d^4 }{ 32 }\) |
||
| Symbol | English | Metric |
| \( J \) = torsional constant | \( in^4 \) | \( mm^4 \) |
| \( d \) = diameter | \( in \) | \( mm \) |
| \( \pi \) = Pi | \(3.141 592 653 ...\) | \(3.141 592 653 ...\) |
| \( r \) = radius | \( in \) | \(mm \) |
Torsional constant (also called the polar moment of inertia or polar second moment of area) for a circular cross-section is a measure of its resistance to torsion (twisting).
