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Unit system  SI derived unit 
Unit of  Force 
Symbol  N 
Named after  Sir Isaac Newton 
In SI base units:  1 N = 1 kg·m/s^{2} 
Unit system  SI derived unit 
Unit of  Force 
Symbol  N 
Named after  Sir Isaac Newton 
In SI base units:  1 N = 1 kg·m/s^{2} 
The newton (symbol: N) is the International System of Units (SI) derived unit of force. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion.
In 1946, 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. The 9th CGPM, held in 1948, then adopted the name "newton" for this unit in resolution 7.^{[1]} This name honors the English physicist and mathematician Isaac Newton, who laid the foundations for most of classical mechanics. The newton thus became the standard unit of force in le Système International d'Unités (SI), or International System of Units.
Newton's second law of motion states that F = ma, where F is the force applied, m is the mass of the object receiving the force, and a is the acceleration of the object. The newton is therefore:^{[2]}
where the following symbols are used for the units:
where
This SI unit is named after Isaac Newton. As with every International System of Units (SI) unit whose name is derived from the proper name of 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 capitalized material such as a title. Note that "degree Celsius" conforms to this rule because the "d" is lowercase. —Based on The International System of Units, section 5.2.
Kilonewtons are often used for stating safety holding values of fasteners, anchors, and more in the building industry. They are also often used in the specifications for rock climbing equipment. The safe working loads in both tension and shear measurements can be stated in kilonewtons. Injection moulding machines, used to manufacture plastic parts, are classed by kilonewton (i.e., the amount of clamping force they apply to the mould).
On the Earth's surface, 1 kN is about 101.97162 kilogramforce of load, so multiplying the kilonewton value by 100 (i.e. using a slightly conservative and easier to calculate value) is a good rule of thumb.^{[3]}
newton (SI unit)  dyne  kilogramforce, kilopond  poundforce  poundal  

1 N  ≡ 1 kg·m/s^{2}  = 10^{5} dyn  ≈ 0.10197 kp  ≈ 0.22481 lb_{F}  ≈ 7.2330 pdl 
1 dyn  = 10^{−5} N  ≡ 1 g·cm/s^{2}  ≈ 1.0197 × 10^{−6} kp  ≈ 2.2481 × 10^{−6} lb_{F}  ≈ 7.2330 × 10^{−5} pdl 
1 kp  = 9.80665 N  = 980665 dyn  ≡ g_{n}·(1 kg)  ≈ 2.2046 lb_{F}  ≈ 70.932 pdl 
1 lb_{F}  ≈ 4.448222 N  ≈ 444822 dyn  ≈ 0.45359 kp  ≡ g_{n}·(1 lb)  ≈ 32.174 pdl 
1 pdl  ≈ 0.138255 N  ≈ 13825 dyn  ≈ 0.014098 kp  ≈ 0.031081 lb_{F}  ≡ 1 lb·ft/s^{2} 
The value of g_{n} as used in the official definition of the kilogramforce is used here for all gravitational units. 
Base  force, length, time  weight, length, time  mass, length, time  

Force (F)  F = m·a = w·a/g  F = m·a/g_{c} = w·a/g  F = m·a = w·a/g  
Weight (w)  w = m·g  w = m·g/g_{c} ≈ m  w = m·g  
System  BG  GM  EE  M  AE  CGS  MTS  SI 
Acceleration (a)  ft/s^{2}  m/s^{2}  ft/s^{2}  m/s^{2}  ft/s^{2}  Gal  m/s^{2}  m/s^{2} 
Mass (m)  slug  hyl  lb_{m}  kg  lb  g  t  kg 
Force (F)  lb  kp  lb_{F}  kp  pdl  dyn  sn  N 
Pressure (p)  lb/in^{2}  at  PSI  atm  pdl/ft^{2}  Ba  pz  Pa 
