Convert Stone (US) (st (US)) to Poundal (pdl) instantly.
About these units
Stone (US) (st (US))
The US stone was an informal and nonstandardized unit occasionally used in the 19th century, with no single agreed-upon value. Unlike the British stone (14 pounds), the US stone varied regionally and by trade context, typically ranging from 12 to 16 pounds, depending on the commodity and location. Farmers, butchers, and merchants sometimes used stones to weigh produce, meat, or livestock, but the lack of uniform regulation prevented it from becoming an official or widely adopted unit. Today, the US stone is entirely obsolete, but references to it appear in historical American trade documents, agricultural records, and pre-standardization weight systems. It serves as a reminder of the diversity of early American measurements before the widespread adoption of the avoirdupois pound.
Poundal (pdl)
The poundal is the unit of force in the foot–pound–second (FPS) system, defined as the force that accelerates a one-pound mass at one foot per second squared. Although a force unit, it interacts with mass units in engineering contexts similarly to inertial mass units. Historically, poundals appeared in older physics textbooks and engineering references before the widespread adoption of SI units. Their use has declined dramatically, but they remain part of the history of classical mechanics education. The poundal exemplifies how many different systems attempted to rationalize force, mass, and acceleration before the international community converged on the SI newton.