Newton 72540 225990425 2008-07-16T10:19:00Z David Underdown 351737 earliest version of article sued Biriths spellings, so should stay that way per [[WP:ENGVAR]] {{Otheruses}} {{Refimprove|date=December 2007}} The '''newton''' (symbol: '''N''') is the [[International System of Units|SI]] [[SI derived unit|derived unit]] of [[force]], named after [[Isaac Newton]] in recognition of his work on [[classical mechanics]]. ==Definition== The newton is the unit of force derived in the SI system; it is equal to the amount of force required to give a mass of one [[kilogram]] an [[acceleration]] of one [[metre]] per [[second]] squared. Algebraically: :<math>{\rm 1~N = 1~\frac{kg\cdot m}{s^2}}.</math> ==Examples== * 1&nbsp;N is the force of earth's gravity on an object with a mass of about 102&nbsp;g ({{frac|1|9.8}}&nbsp;kg) (such as a small apple). * On Earth's surface, a mass of 1&nbsp;kg exerts a force of approximately 9.81&nbsp;N [down] (or 1&nbsp;[[kilogram-force|kgf]]). The approximation of 1&nbsp;kg corresponding to 10&nbsp;N is sometimes used as a rule of thumb in everyday life and in engineering. * The decanewton (daN) = 10&nbsp;N is increasingly used when specifying load bearing capacity of items such as ropes and anti-vibration mounts, being approximately equivalent to the more familiar non-SI unit of force, the [[kilogram-force|kgf]]. * The force of Earth's gravity on a human being with a mass of 70&nbsp;kg is approximately 687&nbsp;N. * The [[dot product]] of force and distance is [[mechanical work]]. Thus, in SI units, a force of 1&nbsp;N exerted over a distance of 1&nbsp;m is 1 N·m of work. The Work-Energy Theorem states that the work done on a body is equal to the change in energy of the body. 1 N·m = 1&nbsp;J ([[joule]]), the SI unit of energy. * It is common to see forces expressed in kilonewtons or kN, where 1&nbsp;kN&nbsp;= 1 000&nbsp;N. * A [[tonne]] (metric ton)=(1 000&nbsp;kg) exerts a force of 9.81&nbsp;kN (or 1 000&nbsp;kgf) under [[standard gravity]] conditions on Earth. ==Notes== {{Units of force}} {{GravEngAbs}} ==References== {{reflist}} * Halliday, Resnick and Walker ''Fundamentals of Physics'', [[John Wiley & Sons]] ISBN 0471470619 ==See also== * [[International System of Units]] (SI) * The [[joule]], which is the SI unit of [[energy]], equivalent to 1 newton exerted over a distance of 1 metre. * The [[pascal (unit)|pascal]], the SI unit of [[pressure]], equivalent to 1 newton acting on an area of 1 [[square metre]]. * The [[kilogram-force]], which is the force exerted by Earth's gravity at sea level on one kilogram of mass. [[Category:Units of force]] [[af:Newton]] [[ar:نيوتن (وحدة)]] [[ast:Newton (unidá)]] [[bn:নিউটন (একক)]] [[zh-min-nan:Newton]] [[be:Ньютан (адзінка вымярэння)]] [[be-x-old:Ньютан (адзінка вымярэньня)]] [[bs:Newton (jedinica)]] [[br:Newton]] [[bg:Нютон]] [[ca:Newton (unitat)]] [[cs:Newton]] [[da:Newton (enhed)]] [[de:Newton (Einheit)]] [[et:Njuuton]] [[es:Newton (unidad)]] [[eo:Neŭtono (unuo)]] [[eu:Newton (unitatea)]] [[fr:Newton (unité)]] [[gd:Newton]] [[gl:Newton (unidade)]] [[zh-classical:牛頓 (單位)]] [[ko:뉴턴]] [[hr:Newton]] [[id:Newton]] [[is:Njúton]] [[it:Newton (unità di misura)]] [[he:ניוטון (מידה)]] [[sw:Nyutoni]] [[ku:Newton (yeke)]] [[la:Newtonium]] [[lv:Ņūtons]] [[lt:Niutonas]] [[hu:Newton (mértékegység)]] [[mk:Њутн]] [[ml:ന്യൂട്ടണ്‍ (അളവ്)]] [[ms:Newton]] [[nl:Newton (eenheid)]] [[new:न्युटन]] [[ja:ニュートン]] [[no:Newton (enhet)]] [[nn:Eininga newton]] [[nds:Newton (Eenheit)]] [[pl:Niuton]] [[pt:Newton]] [[ksh:Newton (Mohß)]] [[ro:Newton]] [[ru:Ньютон (единица измерения)]] [[sco:Newton]] [[simple:Newton]] [[sk:Newton (jednotka)]] [[sl:Newton]] [[sr:Њутн (јединица)]] [[sh:Njutn]] [[fi:Newton]] [[sv:Newton (enhet)]] [[ta:நியூட்டன்]] [[th:นิวตัน]] [[vi:Newton]] [[tr:Newton (birim)]] [[uk:Ньютон]] [[zh-yue:牛頓 (單位)]] [[zh:牛頓 (單位)]]