lb·ft²
pound square foot
Moment of inertiaexact by definition
The pound square foot is one pound of mass at one foot of radius of gyration, exactly 0.0421401100938048 kg·m². The value is exact because the pound and the foot are exactly defined. It is the customary unit for flywheel and rotating machinery inertia.
Watch out: Older machinery literature quotes flywheel effect as WR² or WK² in lb·ft², which is the same quantity as mass moment of inertia. Some sources however use the slug foot squared, which is 32.174 times larger. Check which mass unit the value assumes before using it in a torque calculation.
| 1 lb·ft² | 0.04214011 kg·m² |
Solvers that use moment of inertia