Search results
Results From The WOW.Com Content Network
The foot-poundal (symbol: ft-pdl) is a unit of energy, introduced in 1879, that is part of the Absolute English system of units, which itself is a coherent subsystem of the foot–pound–second system. [1] The foot-poundal is equal to 1/32.174049 that of the more commonly used foot-pound force.
Both energy and torque can be expressed as a product of a force vector with a displacement vector (hence pounds and feet); energy is the scalar product of the two, and torque is the vector product. Although calling the torque unit "pound-foot" has been academically suggested, both are still commonly called "foot-pound" in colloquial usage.
The poundal (symbol: pdl) is a unit of force, introduced in 1877, that is part of the Absolute English system of units, [citation needed] which itself is a coherent subsystem of the foot–pound–second system.
The foot–pound–second system (FPS system) is a system of units built on three fundamental units: the foot for length, the (avoirdupois) pound for either mass or force (see below), and the second for time.
The slug is a derived unit of mass in a weight-based system of measures, most notably within the British Imperial measurement system and the United States customary measures system. Systems of measure either define mass and derive a force unit or define a base force and derive a mass unit [1] (cf. poundal, a
The pound-force is equal to the gravitational force exerted on a mass of one avoirdupois pound on the surface of Earth.Since the 18th century, the unit has been used in low-precision measurements, for which small changes in Earth's gravity (which varies from equator to pole by up to half a percent) can safely be neglected.
Units for other physical quantities are derived from this set as needed. In English Engineering Units, the pound-mass and the pound-force are distinct base units, and Newton's Second Law of Motion takes the form = where is the acceleration in ft/s 2 and g c = 32.174 lb·ft/(lbf·s 2).
Because a foot-poundal is the force required to accelerate a one-pound mass at 1 foot per second squared. Therefore a foot-pound force is 32.1739 times more force than a foot-poundal. Would you agree? A pound-force and a poundal are both units of force. A foot-pound and a foot-poundal are units of energy. They are not units of force.