Newton-metre

 ( Units Of Torque ) 

The newton-metre or newton-meter (also non-hyphenated, newton metre or newton meter; symbol N⋅m or N m) is the unit of torque (also called ) 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 unit is also used less commonly as a unit of work, or energy, in which case it is equivalent to the more common and standard SI unit of energy, the joule.For example: Eshbach's handbook of engineering fundamentals - 10.4 Engineering Thermodynamics and Heat Transfer "In SI units the basic unit of energy is newton-metre". In this usage the metre term represents the distance travelled or displacement in the direction of the force, and not the perpendicular distance from a fulcrum (i.e. the lever arm length) as it does when used to express torque. This usage is generally discouraged,Fundamentals of Physics, 9th edition by Halliday Resnick Walker, p. 309. "The SI unit of torque is the newton-meter. In our discussion of energy we called this combination the joule. But torque is not work and torque should be expressed in newton-meters, not joules. google books link since it can lead to confusion as to whether a given quantity expressed in newton-metres is a torque or a quantity of energy. "Even though torque has the same dimension as energy (SI unit joule), the joule is never used for expressing torque".

Newton-metres and joules are dimensionally equivalent in the sense that they have the same expression in SI base units,

:$1\; \backslash ,\; \backslash text\{N\}\; \{\backslash cdot\}\; \backslash mathrm\{m\}\; =\; 1\; \backslash ,\; \backslash frac\{\backslash text\{kg\}\; \{\backslash cdot\}\; \backslash text\{m\}^2\}\{\backslash text\{s\}^2\}\; \backslash quad\; ,\; \backslash quad\; 1\; \backslash ,\; \backslash mathrm\{J\}\; =\; 1\; \backslash ,\; \backslash frac\{\backslash mathrm\{kg\}\; \{\backslash cdot\}\; \backslash mathrm\{m\}^2\}\{\backslash mathrm\{s\}^2\}$

but are distinguished in terms of applicable kind of quantity, to avoid misunderstandings when a torque is mistaken for an energy or vice versa. Similar examples of dimensionally equivalent units include Pa versus J/m³, Becquerel versus Hertz, and ohm versus ohm per square.

• 1 kilogram-force metre = standard gravity N⋅m Mechanical Engineering Formulas Pocket Guide, p6 Concise encyclopedia of plastics, by Donald V. Rosato, Marlene G. Rosato, Dominick V. Rosato, p621

• 1 newton-metre ≈ 0.73756215 pound-force-feet
• 1 pound-foot ≡ 1 pound-force-foot ≈ 1.35581795 N⋅m
• 1 ounce-inch ≡ 1 ounce-force-inch ≈ 7.06155181 mN⋅m (millinewton-metres)
• 1 dyne-centimetre = 10⁻⁷ N⋅m

• Bending moment
• Spring scale
• Torque tester
• Newton-second, the derived SI unit of impulse