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| [[File:Torque force equivalence at one meter leverage.png|right|300px]]
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| A '''newton metre''' is a [[Physical unit|unit]] of [[torque]] (also called "[[moment (physics)|moment]]") in the [[International System of Units|SI]] system. The symbolic form is '''N m''' or '''N·m'''.<ref>[http://www.bipm.org/en/si/si_brochure/chapter5/5-1.html BIPM - unit symbols]</ref> One newton metre, sometimes hyphenated ''newton-metre'', is equal to the torque resulting from a [[force]] of one [[newton (unit)|newton]] applied perpendicularly to a [[moment arm]] which is one [[metre]] long.
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| It is also used less commonly as a unit of [[work (physics)|work]], or [[energy]], in which case it is equivalent to the more common and standard SI unit of energy, the [[joule]].<ref name=Eshbach>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".</ref> In this very different usage the metre term represents the distance travelled or displacement [[Dot_product#Physics|in the direction]] of the force, and not the [[Cross_product#Mechanics|perpendicular distance]] from a fulcrum as it does when used to express torque. This usage is discouraged by the [[BIPM|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. However, since torque represents energy transferred or expended per angle of revolution, one newton metre of torque is equivalent to one joule per [[radian]].<ref>[http://www.bipm.org/en/si/si_brochure/chapter2/2-2/2-2-2.html BIPM - special names]</ref>
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| Newton metres and joules are "dimensionally equivalent" in the sense that they have the same expression in [[SI base unit]]s:
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| ::<math>1 \, \mathrm{N} \! \cdot \! \mathrm{m} = 1 \frac{\mathrm{kg} \, \mathrm{m}^2}{\mathrm{s}^2} \quad , \quad 1 \, \mathrm{J} = 1 \frac{\mathrm{kg} \, \mathrm{m}^2}{\mathrm{s}^2}</math>
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| Again, N⋅m and J are distinguished in order to avoid misunderstandings where a torque is mistaken for an energy or vice-versa. Similar examples of "dimensionally equivalent" units include [[Becquerel]] versus [[Hertz]], and [[ohm]]s versus [[ohms per square]].
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| {{clear}}
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| ==Conversion factors==
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| *1 newton metre = 0.7375621 [[pound-foot (torque)|pound-foot]] (often "foot-pound")
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| *1 [[kilogram-force]] metre = 9.80665 Nm<ref>[http://books.google.com/books?id=hAFRfIZMzrwC&pg=PA6 ''Mechanical Engineering Formulas Pocket Guide'', p6]</ref><ref>[http://books.google.com/books?id=0g9QjxsbqmUC&pg=PA621 ''Concise encyclopedia of plastics'', by Donald V. Rosato, Marlene G. Rosato, Dominick V. Rosato, p621]</ref>
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| *1 [[pound-foot (torque)|pound-foot]] (often "foot-pound") = 1 [[pound force]] foot ˜ 1.3558 Nm
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| *1 inch [[ounce-force]] = 7.0615518 mNm
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| *1 [[dyne]] centimetre = 10<sup>−7</sup> Nm
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| *1 [[joule]] = 1 Nm
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| ==See also==
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| *[[Bending moment]]
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| *[[Spring scale]]
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| *[[Torque tester]]
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| ==References==
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| {{reflist}}
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| [[Category:Units of torque]]
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| [[Category:SI derived units]]
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Nothing to tell about myself I think.
Yes! Im a part of wmflabs.org.
I really hope I am useful at all
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