poundforce
Pound-force (lbf) is a unit of force used in the United States customary and related British gravitational systems. It is defined as the force required to accelerate a mass of one pound‑mass (lbm) at standard gravity, g0, which is 32.174 ft/s^2. Equivalently, it is the weight of a one-pound mass under standard gravity. In engineering practice, the relationship among force, mass, and acceleration in these units is F(lbf) = m(lbm) × a(ft/s^2) / g_c, where g_c = 32.174 lbm·ft/(lbf·s^2).
One pound-force is exactly equal to 4.448221615 N in SI units (approximately). The unit is commonly used
Pound-force is distinct from the pound-mass (lbm). The avoirdupois pound is a unit of mass, whereas the
The pound-force forms part of the English engineering units system and remains in use in some engineering