For example, when a stone is released, it falls down because it is pulled by the Earth’s force of gravity. ^ European Economic Community, Council Directive of 18 October 1971 on the approximation of the laws of the Member States relating to units of measurement (Directive 71/354/EEC), Annex, Chapter III.Physics defines force as an influence that changes the movement of a body, be it external movement or movement within the body, such as changing its shape."The American Engineering System of Units and Its Dimensional Constant g c". "English Engineering Units and Their Dimensions". In the past the units for Vickers hardness were kg/mm2 in Table 12.6 we use the SI units of GPa. Materials Science and Engineering: An Introduction. It is not tensile strength, which by definition is the force per unit area. Breaking load (BL): The strength of a wire and its actual force (usually given in grams, grams-force, mN, etc.) required to break a particular wire in a tensile pull. Wire Bonding in Microelectronics (3rd ed.). The recommended tension for spokes in bicycle wheels can be as low as 80 Kilograms force (Kfg) and as high as 230 Kilograms force. "Balancing wheel tension with the TM-1 Spoke Tension Metre". ^ Resolution 7 of the 9th meeting of the CGPM (1948).^ Proceedings of the 5th General Conference on Weights and Measures, 1913, pages 51 and 56, (french).^ Proceedings of the 3rd General Conference on Weights and Measures, 1901, pages 62–64 and 68, (french).^ NIST Guide to the SI, Chapter 5: Units Outside the SI.^ BIPM SI brochure Archived at the Wayback Machine, chapter 2.2.2.^ a b NIST Guide for the Use of the International System of Units (SI) Special Publication 811, (1995) page 51.^ The international system of units (SI) Archived at the Wayback Machine – United States Department of Commerce, NIST Special Publication 330, 2008, p.Three approaches to metric units of mass and force or weight In addition, the kilogram force was the standard unit used for Vickers hardness testing. It is still in use for some purposes, for example, it is used for the tension of bicycle spokes, for informal references to pressure in kilograms per square centimetre (1 kp/cm 2) which is the technical atmosphere (at) and very close to 1 bar and the standard atmosphere (atm), for the draw weight of bows in archery, for the strength of bond wire in grams-force, and to define the " metric horsepower" (PS) as 75 metre-kiloponds per second. Prior to this, the unit was widely used in much of the world. The kilogram-force has never been a part of the International System of Units (SI), which was introduced in 1960. Instead, the newton was proposed in 1913 and accepted in 1948. Even then, the proposal to define kilogram-force as standard unit of force was explicitly rejected. The gram-force and kilogram-force were never well-defined units until the CGPM adopted a standard acceleration of gravity of 9.80665 m/s 2 for this purpose in 1901, though they had been used in low-precision measurements of force before that time. Kilogram-force is a non-standard unit and is classified in the International System of Units (SI) as a unit that is not accepted for use with SI. Similarly, a gram-force is 9.806 65 mN, and a milligram-force is 9.806 65 μN. Therefore, one kilogram-force is by definition equal to 9.806 65 N. That is, it is the weight of a kilogram under standard gravity. The kilogram-force is equal to the magnitude of the force exerted on one kilogram of mass in a 9.806 65 m/s 2 gravitational field ( standard gravity, a conventional value approximating the average magnitude of gravity on Earth). It does not comply with the International System of Units (SI) and is deprecated for most uses. The kilogram-force ( kgf or kg F), or kilopond ( kp, from Latin: pondus, lit.'weight'), is a non-standard gravitational metric unit of force. For other uses, see KGF (disambiguation).
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