FPS system
BI A system of units that uses the foot, the pound, and the second as base units. (Compare the m.k.s. system and its contemporary form, the SI system, with its base units the metre, the kilogram, and the second. See also f.g.s. system.)
In a physics context, the f.p.s. system has the pound as a unit of mass; the distinctive coherent units include:
• length: ft = foot (= 0.3048 m);
• mass: lb or lb-m = pound-mass (= 0.453 592~ kg);
• time: s = second;
• force: pdl = poundal = ft·lb-m·s-2 (= 0.138 255~ N, 0.031 081 0~ lb-f);
• dynamic viscosity: poundal·second per sq. foot = ft·lb-m·s-2 (= 0.671 968~ N·s·m-2).
In an engineering context, the f.p.s. system has the pound as a unit of weight, i.e. a force (called the
