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.

Related Topics:
Law of universal gravitation - Force - Mass - Inversely proportional to the square of the distance

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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.

Related Topics:
Constant of proportionality - Physical constant - Newton - Einstein - General relativity

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

Related Topics:
SI - CODATA

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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.

Related Topics:
Relatively weak - SUV - Centers of gravity - Metre - Weight

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