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The standard acceleration of gravity or standard acceleration of free fall, often called simply standard gravity and denoted by ɡ 0 or ɡ n, is the nominal gravitational acceleration of an object in a vacuum near the surface of the Earth.
It does not include the reduction of constraint force that we perceive as a reduction of gravity due to the rotation of Earth, and some of gravity being counteracted by centrifugal force. There are significant uncertainties in the values of r and m 1 as used in this calculation, and the value of G is also rather difficult to measure precisely.
By the 1930s, Paul Dirac developed the hypothesis that gravitation should slowly and steadily decrease over the course of the history of the universe. [112] Alan Guth and Alexei Starobinsky proposed in 1980 that cosmic inflation in the very early universe could have been driven by a negative pressure field, a concept later coined ' dark energy ...
The unit definition does not vary with location—the g-force when standing on the Moon is almost exactly 1 ⁄ 6 that on Earth. The unit g is not one of the SI units, which uses "g" for gram. Also, " g " should not be confused with " G ", which is the standard symbol for the gravitational constant . [ 6 ]
In physics, gravity (from Latin gravitas 'weight' [1]) is a fundamental interaction primarily observed as a mutual attraction between all things that have mass.Gravity is, by far, the weakest of the four fundamental interactions, approximately 10 38 times weaker than the strong interaction, 10 36 times weaker than the electromagnetic force, and 10 29 times weaker than the weak interaction.
The Big Bang is a physical theory that describes how the universe expanded from an initial state of high density and temperature. [1] The concept of an expanding universe was scientifically originated by physicist Alexander Friedmann in 1922 with the mathematical derivation of the Friedmann equations.
The Central Intelligence Agency (CIA / ˌ s iː. aɪ ˈ eɪ /) is a civilian foreign intelligence service of the federal government of the United States tasked with advancing national security through collecting and analyzing intelligence from around the world and conducting covert operations.
All isotopes of uranium are radioactive because the strong nuclear force does not prevail over electromagnetic repulsion in nuclides containing more than 82 protons. [109] Nevertheless, the two most stable isotopes, 238 U and 235 U, have half-lives long enough to occur in nature as primordial radionuclides , with measurable quantities having ...