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Tony Stark
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Has there been any recent changes in the G constant value?
This just means that GMearth varies slightly over time.rootone said:G cannot be a constant since the mass of the Earth is not a constant.
In fact several tonnes of micrometoric dust is accumulated every day.
Although that makes no significant difference to the measure of G over the course of a human life time, it might make a difference on geologic time scales.
Under the assumption that the physics of type Ia supernovae are universal, analysis of observations of 580 type Ia supernovae has shown that the gravitational constant has varied by less than one part in ten billion per year over the last nine billion years.
You are confusing G, the Newtonian gravitational constant, with g, gravitational acceleration at the surface of the Earth. Big G is dimensional physical constant, the G in [itex]F=\frac {Gm_1m_2}{r^2}[/itex] (Newton's law of gravitation). That is modern notation; Newton himself didn't express his law of gravitation that way, nor did Henry Cavendish, the first to measure G (but only after the fact). Cavendish intent was to "weigh the Earth".rootone said:G cannot be a constant since the mass of the Earth is not a constant.
In fact several tonnes of micrometoric dust is accumulated every day.
The G constant, also known as the gravitational constant, is a fundamental physical constant that represents the strength of the gravitational force between two objects. It is important because it is used in many equations and calculations related to gravity and the behavior of celestial bodies.
The G constant is typically measured using a torsion balance experiment, where two large masses are suspended on a wire and their gravitational attraction causes the wire to twist. By measuring the amount of twist and the distance between the masses, the G constant can be calculated.
There have been discrepancies in the value of the G constant measured by different experiments, leading to the possibility that it may have changed over time. However, most recent measurements have shown that the value of G is likely constant within a small margin of error.
The most recent and accurate measurement of the G constant was made in 2018 by the CODATA (Committee on Data for Science and Technology), which determined the value to be 6.67430(15) x 10^-11 m^3 kg^-1 s^-2.
The G constant is a crucial component in our understanding of gravity and its effects on the universe. It helps us calculate the force of gravity between objects, determine the mass and density of celestial bodies, and make predictions about the behavior of objects in space.