The British thermal unit is a measure of heat, which is a form of energy. It was originally defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. It is also part of the United States customary units. The SI unit for energy is the joule (J); one BTU equals about 1,055 J.
Horsepower (hp) is a unit of measurement of power, or the rate at which work is done, usually in reference to the output of engines or motors. There are many different standards and types of horsepower. Two common definitions used today are the mechanical horsepower, which is about 745.7 watts, and the metric horsepower, which is approximately 735.5 watts.
The joule is the unit of energy in the International System of Units (SI). It is equal to the amount of work done when a force of one newton displaces a mass through a distance of one metre in the direction of that force. It is also the energy dissipated as heat when an electric current of one ampere passes through a resistance of one ohm for one second. It is named after the English physicist James Prescott Joule (1818–1889).
In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force. It describes the rate of change of angular momentum that would be imparted to an isolated body.
United States customary units form a system of measurement units commonly used in the United States and most U.S. territories, since being standardized and adopted in 1832. The United States customary system developed from English units that were in use in the British Empire before the U.S. became an independent country. The United Kingdom's system of measures was overhauled in 1824 to create the imperial system, which was officially adopted in 1826, changing the definitions of some of its units. Consequently, while many U.S. units are essentially similar to their imperial counterparts, there are significant differences between the systems.
The pound of force or pound-force is a unit of force used in some systems of measurement, including English Engineering units and the foot–pound–second system.
The cubic inch is a unit of volume in the Imperial units and United States customary units systems. It is the volume of a cube with each of its three dimensions being one inch long which is equivalent to 1/231 of a US gallon.
The newton-metre or newton-meter is the unit of torque in the International System of Units (SI). One newton-metre is equal to the torque resulting from a force of one newton applied perpendicularly to the end of a moment arm that is one metre long.
The foot-pound force is a unit of work or energy in the engineering and gravitational systems in United States customary and imperial units of measure. It is the energy transferred upon applying a force of one pound-force (lbf) through a linear displacement of one foot. The corresponding SI unit is the joule, though in terms of energy, one joule is not equal to one foot-pound.
The poundal is a unit of force, introduced in 1877, that is part of the Absolute English system of units, which itself is a coherent subsystem of the foot–pound–second system.
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. A slug is defined as a mass that is accelerated by 1 ft/s2 when a net force of one pound (lbf) is exerted on it.
Muzzle energy is the kinetic energy of a bullet as it is expelled from the muzzle of a firearm. Without consideration of factors such as aerodynamics and gravity for the sake of comparison, muzzle energy is used as a rough indication of the destructive potential of a given firearm or cartridge. The heavier the bullet and especially the faster it moves, the higher its muzzle energy and the more damage it will do.
The AGM-136A Tacit Rainbow was a United States military anti-radiation missile program run from 1982 to 1991.
Both the British imperial measurement system and United States customary systems of measurement derive from earlier English unit systems used prior to 1824 that were the result of a combination of the local Anglo-Saxon units inherited from Germanic tribes and Roman units.
The foot–pound–second system is a system of units built on three fundamental units: the foot for length, the (avoirdupois) pound for either mass or force, and the second for time.
The pound per square inch or, more accurately, pound-force per square inch, is a unit of measurement of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force with magnitude of one pound-force applied to an area of one square inch. In SI units, 1 psi is approximately 6,895 pascals.
A pound-foot (lb⋅ft), abbreviated from pound-force foot, is a unit of torque representing one pound of force acting at a perpendicular distance of one foot from a pivot point. Conversely one foot pound-force is the moment about an axis that applies one pound-force at a radius of one foot.
A coherent system of units is a system of units of measurement used to express physical quantities that are defined in such a way that the equations relating the numerical values expressed in the units of the system have exactly the same form, including numerical factors, as the corresponding equations directly relating the quantities. It is a system in which every quantity has a unique unit, or one that does not use conversion factors.
The imperial and US customary measurement systems are both derived from an earlier English system of measurement which in turn can be traced back to Ancient Roman units of measurement, and Carolingian and Saxon units of measure.
In engineering and physics, gc is a unit conversion factor used to convert mass to force or vice versa. It is defined as