نيوتن (وحدة)

newton
One Newton, illustrated (transparent background).svg
Visualization of one newton of force
معلومات عامة
نظام الوحداتSI
وحدة قياسforce
الرمزN 
مسمى على اسمSir Isaac Newton
التحويلات
1 N في ...... يساوي ...
   SI base units   1 kgms−2
   CGS units   105 dyn
   Imperial units   0.224809 lbf

نيوتن Newton هي وحدة القوة في نظام المتر كيلوگرام ثانية، وهي القوة التي لو أثرت على كتلة كيلوگرام واحد لأكسبتها تعجيل مقداره متر في الثانية في الثانية.

سميت هذه الوحدة بالنيوتن تخليدا للعالم سير إسحق نيوتن العالم الفيزيائي والرياضي الإنكليزي.

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التعريف

A newton is defined as (it is a derived unit which is defined in terms of the SI base units).[1] One newton is, therefore, the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in the direction of the applied force.[2]

The units "metre per second squared" can be understood as measuring a rate of change in velocity per unit of time, i.e. an increase in velocity by 1 metre per second every second.

In 1946, the Conférence Générale des Poids et Mesures (CGPM) Resolution 2 standardized the unit of force in the MKS system of units to be the amount needed to accelerate 1 kilogram of mass at the rate of 1 metre per second squared. In 1948, the 9th CGPM Resolution 7 adopted the name newton for this force.[3] The MKS system then became the blueprint for today's SI system of units. The newton thus became the standard unit of force in the Système international d'unités (SI), or International System of Units.

This SI unit is named after Isaac Newton. As with every International System of Units (SI) unit named for a person, the first letter of its symbol is upper case (N). However, when an SI unit is spelled out in English, it should always begin with a lower case letter (newton)—except in a situation where any word in that position would be capitalized, such as at the beginning of a sentence or in material using title case. Note that "degree Celsius" conforms to this rule because the "d" is lowercase.— Based on The International System of Units, section 5.2.

In more formal terms, Newton's second law of motion states that the force exerted on an object is directly proportional to the acceleration hence acquired by that object, thus:[4]

where m represents the mass of the object undergoing an acceleration a. As a result, the newton may be defined in terms of the kilogram (), metre (), and second () as


أمثلة

At average gravity on Earth (conventionally, ), a kilogram mass exerts a force of about 9.8 newtons.

  • An average-sized apple at 200 g exerts about two newtons of force at Earth's surface, which we measure as the apple's weight on Earth.
(where 62 kg is the world average adult mass).[5]

كيلونيوتن

A carabiner used in rock climbing, with a safety rating of 26 kN when loaded along the spine with the gate closed, 8 kN when loaded perpendicular to the spine, and 10 kN when loaded along the spine with the gate open.

It is common to see forces expressed in kilonewtons (kN), where 1 kN = 1000 N. For example, the tractive effort of a Class Y steam train locomotive and the thrust of an F100 jet engine are both around 130 kN.

One kilonewton, 1 kN, is equivalent to 102.0 kgf, or about 100 kg of load under Earth gravity.

.

So, for example, a platform that shows it is rated at 321 kilonewtons (72,000 lbf) will safely support a 32,100-kilogram (70,800 lb) load.

Specifications in kilonewtons are common in safety specifications for:

عوامل التحويل

قالب:Units of force قالب:GravEngAbs

سوابق النظام الدولي للوحدات
مضاعفات اسم السابقة ديسا هكتو كيلو ميگا گيگا تيرا پيتا إكسا زيتا يوتا
رمز السابقة da h k M G T P E Z Y
العامل 100 101 102 103 106 109 1012 1015 1018 1021 1024
 
المضاعفات الفرعية اسم السابقة           ديسي سنتي ملي ميكرو نانو پيكو فمتو اتو زپتو يوكتو
رمز السابقة d c m μ n p f a z y
العامل 100 10−1 10−2 10−3 10−6 10−9 10−12 10−15 10−18 10−21 10−24

انظر أيضاً

References

  1. ^ Bureau International des Poids et Mesures (2019). The International System of Units (SI) (PDF) (9 ed.). Bureau International des Poids et Mesures (BIPM). p. 137.
  2. ^ "Newton | unit of measurement". Encyclopedia Britannica. 2020-12-17. Archived from the original on 2019-09-27. Retrieved 2019-09-27.
  3. ^ The International System of Units (SI) (1977 ed.). U.S. Department of Commerce, National Bureau of Standards. 1977. p. 17. ISBN 90112101554977. Archived from the original on 2016-05-11. Retrieved 2015-11-15. {{cite book}}: Check |isbn= value: length (help)
  4. ^ "Table 3. Coherent derived units in the SI with special names and symbols". The International System of Units (SI). International Bureau of Weights and Measures. 2006. Archived from the original on 2007-06-18.
  5. ^ Walpole, Sarah Catherine; Prieto-Merino, David; et al. (18 June 2012). "The weight of nations: an estimation of adult human biomass". BMC Public Health. 12 (12): 439. doi:10.1186/1471-2458-12-439. PMC 3408371. PMID 22709383.

الهامش

وحدات القوة
نيوتن
(وحدات SI)
داين كيلوجرام-قوة
(Kilopond)
رطل-قوة باوندال
1 نيوتن ≡ 1 كجم·م/ث² = 105 داين ≈ 0.10197 كجم-قوة ≈ 0.22481 رطلق ≈ 7.2330 باوندال
1 داين = 10−5 نيوتن ≡ 1 جم·سم/ث² ≈ 1.0197 كجم-قوة ≈ 2.2481 رطلق ≈ 7.2330 باوندال
1 كجم- قوة = 9.80665 نيوتن = 980665 داين gn·(1 كجم) ≈ 2.2046 رطلق ≈ 70.932 باوندال
1 رطلق ≈ 4.448222 نيوتن ≈ 444822 داين ≈ 0.45359 كجم-قوة gn·(1 lb) ≈ 32.174 باوندال
1 باوندال ≈ 0.138255 نيوتن ≈ 13825 داين ≈ 0.014098 كجم-قوة ≈ 0.031081 رطلق ≡ 1 رطل·قدم/ث²
قيمة gn المستخدمة هنا لجميع وحدات الجاذبية مساوية لقيمنها في التعريف الرسمي للكيلوجرام-قوة.