Moment of inertia of a right triangle
Enter the legs to get the area, the centroid position and the moments of inertia about the centroidal axes.
Formulas
About this calculator
The centroid of a triangle sits a third of the height above the base, so the extreme fibres are at unequal distances: h/3 below and 2h/3 above. The section modulus is taken with the larger arm, which is what limits the bending moment.
Frequently asked questions
At the intersection of the medians — h/3 above the base and b/3 from the vertical leg.
About the base a triangle gives bh³/12; transferring to the centroidal axis subtracts A·(h/3)², which leaves bh³/36.