ft⁴

foot to the fourth

Area moment of inertiaexact by definition

The foot to the fourth power is exactly 0.0086309748412416 m⁴, since the foot is exactly 0.3048 m and the fourth power terminates. It is rarely used for structural sections, which are too small for it, and appears mainly in hydraulic and geotechnical work where the bending members are very large.

1 ft⁴ 8,630,974,800 mm⁴