Gravitational constant

According to the law of universal gravitation, the attractive force between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance between them.

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: F = G rac{m_1 m_2}{r^2}

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The constant of proportionality is called {G} , the gravitational constant, the universal gravitational constant, Newton's constant, and colloquially big G. The gravitational constant is a fundamental physical constant which appears in Newton's law of universal gravitation and in Einstein's theory of general relativity.

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In SI units, the 2002 CODATA recommended value of the gravitational constant is

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: G = left(6.6742 plusmn 0.001 ight) imes 10^{-11} mbox{N} mbox{m}^2 mbox{kg}^{-2} ,

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:: = left(6.6742 plusmn 0.001 ight) imes 10^{-11} mbox{m}^3 mbox{s}^{-2} mbox{kg}^{-1} ,

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Another authoritative estimate is given by the International Astronomical Union (see Standish, 1995).

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The gravitational force is relatively weak. As an example, two SUVs, each with a mass of 3000 kilograms and placed with their centers of gravity 3 metres apart, will attract each other with a force of about 67 micronewtons. This force is approximately equal to the weight of a large grain of sand.

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Law of universal gravitation: The law of universal gravitation states that gravitational force between masses decreases with the distance between them, according to an inverse-square law. In addition, the theory notes that the greater an object's mass, the greater its gravitational force on another mass. Newton published his arg...

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Gravitational constant related Images and Photos (experimental)

Constant Nymph, The (Remastered)	The Constant Gardener	The Constant Gardener	The Constant Gardener DVD (Widescreen)
The Constant Nymph 1943	Henri Benjamin Constant de Rebecque	Henri Benjamin Constant de Rebecque	Dream Theater - Constant Motion
Portrait of Benjamin Constant de Rebecque