Summary
In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). It describes the rate of change of angular momentum that would be imparted to an isolated body. The concept originated with the studies by Archimedes of the usage of levers, which is reflected in his famous quote: "Give me a lever and a place to stand and I will move the Earth". Just as a linear force is a push or a pull applied to a body, a torque can be thought of as a twist applied to an object with respect to a chosen point. Torque is defined as the product of the magnitude of the perpendicular component of the force and the distance of the line of action of a force from the point around which it is being determined. The law of conservation of energy can also be used to understand torque. The symbol for torque is typically , the lowercase Greek letter tau. When being referred to as moment of force, it is commonly denoted by M. In three dimensions, the torque is a pseudovector; for point particles, it is given by the cross product of the displacement vector and the force vector. The magnitude of torque applied to a rigid body depends on three quantities: the force applied, the lever arm vector connecting the point about which the torque is being measured to the point of force application, and the angle between the force and lever arm vectors. In symbols: where is the torque vector and is the magnitude of the torque, is the position vector (a vector from the point about which the torque is being measured to the point where the force is applied), and r is the magnitude of the position vector, is the force vector, and F is the magnitude of the force vector, denotes the cross product, which produces a vector that is perpendicular both to r and to F following the right-hand rule, is the angle between the force vector and the lever arm vector. The SI unit for torque is the newton-metre (N⋅m). For more on the units of torque, see .
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related publications (16)
Related concepts (100)
Torque
In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). It describes the rate of change of angular momentum that would be imparted to an isolated body. The concept originated with the studies by Archimedes of the usage of levers, which is reflected in his famous quote: "Give me a lever and a place to stand and I will move the Earth". Just as a linear force is a push or a pull applied to a body, a torque can be thought of as a twist applied to an object with respect to a chosen point.
Work (physics)
In physics, work is the energy transferred to or from an object via the application of force along a displacement. In its simplest form, for a constant force aligned with the direction of motion, the work equals the product of the force strength and the distance traveled. A force is said to do positive work if when applied it has a component in the direction of the displacement of the point of application. A force does negative work if it has a component opposite to the direction of the displacement at the point of application of the force.
Statics
Statics is the branch of classical mechanics that is concerned with the analysis of force and torque acting on a physical system that does not experience an acceleration, but rather, is in static equilibrium with its environment. If is the total of the forces acting on the system, is the mass of the system and is the acceleration of the system, Newton's second law states that (the bold font indicates a vector quantity, i.e. one with both magnitude and direction). If , then .
Show more
Related courses (56)
EE-382: Electrical machines (for ME)
L'objectif de ce cours est d'acquérir les connaissances de base liées aux machines électriques (conversion électromécanique). Le cours porte sur le circuit magnétique, le transformateur, les machines
ME-202: Mechanical systems
Ce cours vise à approfondir la compréhension des lois de fonctionnement de plusieurs principes mécaniques majeurs et largement utilisés en construction de machines, en vue d'être capable d'en faire le
MICRO-314: Actuators and Electromagnetic systems II
Les étudiants seront capables de modéliser, de simuler et de mesurer des actionneurs électromagnétiques et des moteurs électriques.
Show more
Related lectures (600)
Systems of Forces in 3D
Explores systems of forces in three dimensions, emphasizing moments and couples, equilibrium, and scalar components.
Introduction to Structural Mechanics
Introduces resultants in 3D, equilibrium in 2D, and free-body diagrams for structural analysis.
Statics: Forces and Moments
Explores statics, focusing on equilibrium conditions, force torques, and virtual work principles.
Show more
Related MOOCs (11)
Conversion electromécanique I
Circuits magnétiques, aimants permanents, conversion électromécanique, actionneurs.
Conversion electromécanique I
Circuits magnétiques, aimants permanents, conversion électromécanique, actionneurs.
Conversion electromécanique II
Principes de fonctionnement, construction, calcul et applications des moteurs electriques.
Show more