Convert Quarter (US) (qr (US)) to Pound-force Square Second/Foot (lbf·s²/ft) instantly.
About these units
Quarter (US) (qr (US))
The US quarter equals 25 pounds, serving as a smaller commercial subdivision of the hundredweight. It was used for pricing agricultural goods, livestock feed, and some industrial materials. Its convenience arises from the fact that four quarters make a hundredweight, simplifying scaling between small and medium quantities. Today it is mostly of historical interest, but agricultural economists still encounter it when analyzing archival data.
Pound-force Square Second/Foot (lbf·s²/ft)
This unit is part of the British Gravitational System, where mass is defined from force rather than the other way around. It can be interpreted as an inertial mass unit, since applying 1 pound-force to it would produce an acceleration of 1 foot per second squared. Historically, before the SI system clarified the distinction between force and mass, engineering fields often used mixed systems where pounds could represent either force (lbf) or mass (lbm). The unit lbf·s²/ft was introduced to straighten out these ambiguities in dynamic calculations such as impact forces, mechanical oscillations, and safety load computations. Today, the unit survives mostly in engineering textbooks, legacy calculations, and historical documentation. It demonstrates how complex and inconsistent measurement systems once were, and why global scientific communities moved toward SI clarity.