Newton metre
Encyclopedia
A newton metre is a unit of torque
(also called "moment") in the SI
system. The symbolic form is N m or N·m, and sometimes hyphenated newton-metre. One newton metre is equal to the torque resulting from a force
of one newton applied perpendicularly to a moment arm which is one metre long.
It is also used less commonly as a unit of energy, in which case it is equivalent to the more common and standard SI unit of energy, the joule
. In this very different usage the metre term represents the distance traveled or displacement in the direction of the force, and not the perpendicular distance from a fulcrum as it does when used to express torque. This usage is discouraged by the SI authority, since it can lead to confusion as to whether a given quantity expressed in newton metres is a torque or a quantity of energy.
N·m in terms of torque can be used in to calculate joules consumed by multiplying it by the angle (in radians) through which a body rotates in the direction of the torque. Or it can be used to calculate power output in watts by multiplying it by the speed of rotation (in radians per second).
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
(also called "moment") in the SI
Si
Si, si, or SI may refer to :- Measurement, mathematics and science :* International System of Units , the modern international standard version of the metric system...
system. The symbolic form is N m or N·m, and sometimes hyphenated newton-metre. One newton metre is equal to the torque resulting from a force
Force
In physics, a force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. In other words, a force is that which can cause an object with mass to change its velocity , i.e., to accelerate, or which can cause a flexible object to deform...
of one newton applied perpendicularly to a moment arm which is one metre long.
It is also used less commonly as a unit of energy, in which case it is equivalent to the more common and standard SI unit of energy, the joule
Joule
The joule ; symbol J) is a derived unit of energy or work in the International System of Units. It is equal to the energy expended in applying a force of one newton through a distance of one metre , or in passing an electric current of one ampere through a resistance of one ohm for one second...
. In this very different usage the metre term represents the distance traveled or displacement in the direction of the force, and not the perpendicular distance from a fulcrum as it does when used to express torque. This usage is discouraged by the SI authority, since it can lead to confusion as to whether a given quantity expressed in newton metres is a torque or a quantity of energy.
N·m in terms of torque can be used in to calculate joules consumed by multiplying it by the angle (in radians) through which a body rotates in the direction of the torque. Or it can be used to calculate power output in watts by multiplying it by the speed of rotation (in radians per second).
Conversion factors
- 1 newton meter = 0.7375621 foot-pound forceFoot-pound forceThe foot-pound force, or simply foot-pound 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 on applying a force of 1 pound-force through a displacement of 1 foot...
(often "foot-pound") - 1 kilogram-forceKilogram-forceA kilogram-force , or kilopond , is a gravitational metric unit of force. It is equal to the magnitude of the force exerted by one kilogram of mass in a gravitational field...
meter = 9.80665 N·m - 1 foot-pound forceFoot-pound forceThe foot-pound force, or simply foot-pound 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 on applying a force of 1 pound-force through a displacement of 1 foot...
(often "foot-pounds") = 1k pound-forcePound-forceThe pound force is a unit of force in some systems of measurement including English engineering units and British gravitational units.- Definitions :...
foot (often "pound-foot") ≈ 1.3558 N·m - 1 inch ounce-force = 7.0615518 mN·m
- 1 dyneDyneIn physics, the dyne is a unit of force specified in the centimetre-gram-second system of units, a predecessor of the modern SI. One dyne is equal to exactly 10 µN...
centimetre = 10−7 N·m