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Let the two bodies involved have masses $m_1, m_2$. Start with Newton's second law $$F = ma$$ where $a$ is acceleration. The gravitational force on body 2 from body 1 is given by $$F_{21} = \frac{G m_1 m_2}{|r_{21}|^3}r_{21}$$ where $r_{21}$ is the relative position vector for the two bodies in question. The force on body 1 from body two is of course ...


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There are several major types of black hole, and each forms differently: Quantum black holes - these aren't currently proven to exist, but many scientists think they are likely. These are microscopic black holes, which are believed to have formed in the Big Bang, though they can be created wherever there is enough energy. Stellar-mass black holes. These ...


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The what if is superficial, it could never exist, but if one were to imagine, then; the out come would be very bleak for Earth and Mankind alike. Jupiter has the strongest gravitational pull in our solar system and most likely in our galaxy. It is one of our solar system's gas planets,or Jovian planets; it's core is made of H3, the gas succumbs to the ...


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Yes The gravitational field from an object does extend infinitely far out into space, if there is an infinite space for it to fill. There isn't any sort of limit to how far an object's gravitational influence can travel. However, there is a catch: Gravity travels at a finite speed (the speed of light). If gravity propagated infinitely fast, any two objects ...


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None of us would know that the Sun had actually disappeared until the approximate eight minute point had passed. At that point, we would all be very quickly screaming and panicking at the absolute and total darkness which would suddenly replace all normal daylight. The gravitational concerns would be the least of our worries, I think. If it happened at ...


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Let me see if I can ask a different question that will help you understand why these other answers are correct. If you weigh yourself at night (when the Earth's gravity and the Sun's gravity are pulling in the same direction), do you weigh significantly more than you do during the day (when the Sun would be 'pulling you up'? The answer is no, because the ...


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Weighlessness is a property of gravitational freefall. When you're standing on the surface of the Earth, the weight you feel is the reaction force of the Earth's surface stopping you from falling, i.e., weight is caused by the failure of gravitational freefall. There is no relevant difference between a round orbit and a radial plunge orbit. They're both ...


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In a sense, this is one of those "If I break the laws of physics, what do the laws of physics say will happen" kinds of questions. Ignoring that, a 150 pound person would still weigh about 150 pounds if the Earth miraculously stopped orbiting the Sun. Almost all of a person's weight results from resistance to the Earth's gravity field. The tidal ...


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The two terms are used in answering different questions. Hill Sphere: given a large mass (eg Sun) and a small mass (eg Earth), can a tiny mass (eg Moon) find a stable orbit around the small mass? (If the tiny mass goes outside the Hill Sphere of the small mass, no.) SOI: given two large mass objects and a small object between them, (eg sending a probe ...


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Gravity is force that comes from one object pulling on another object. This causes a rotation around a center of masses. In a case of the sun pulling the earth, the center of mass is on the sun's surface and thus the earth rotates around the sun. The force pulling the earth towards the center of mass between the sun and earth is called a centripetal force or ...


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Immediate expansion. I would like to break it down into a steps starting with smaller magnitude and growing larger as we go. However, a few assumptions must be made for this to make sense (since your question does break the laws of physics): Since gravity is mass-dependent in the equation F=GMm/r^(2) we are not assuming that everything suddenly has no mass ...


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I expect stars would belch mightily, neutron stars and black holes would explode. Stars are only held at their steady state size by the opposed forces of gravity and radiation, so eliminating gravity for 1 second will cause expansion, followed by collapse as gravity kicks in again. A Neutron star's compactness gives it a surface gravity of up to 7×10^12 ...


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Nothing much. If it is only for one second, then depending on where you are on Earth you would start floating for one second going up somewhat (but not very much). If you are on the equator you will have a velocity (parallel to the Earth's rotation) of about 465m/s. In that second the Earth will have rotated 0.004°. This means that you will have increased ...


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Interesting but light too effected by gravity, as it moves opposite to gravity it's wavelength length decreases but it is negligible. And I'm sure that light is effected by gravity because light cannot pass through a blackhole due to its high gravity. If light is not effected by gravity then it can pass through a blackhole and we can see inside a blackhole. ...


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Most of the light energy in the universe is still in the cosmic microwave background (CMB). Spring 2011 UC Berkeley Physics 250 class materials calculate from the fact that $T=2.73$ for the CMB: It follows that photons contribute only $0.0000485$ of the closure density.


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The dipole in the microwave background indicates motion of the Milky Way and thus of the whole Local Group, at least, at about 600 km/s in a certain direction. The straightforward explanation is that the density irregularities nearby from superclusters and voids result in a net gravitational acceleration that, over the age of the universe, resulted in this ...


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We wouldn't feel the ejection of another planet off the solar system, since the attractive force of distant planets to Earth is very low. Only close encounters of Earth with other planets would cause noticeable up to severe changes on Earth. This would be caused mainly by tidal forces due to different acceleration for different parts of Earth, or by ...


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This looks like it's going to be a "No, it's not possible, because . . ." answer, but hopefully it answers your question. Your proposal is that the Milky Way is a brain, and that the stars are like neurons, correct? I'm not a biologist or neuroscientist, but I do know one characteristic of neurons that helps them do their job: They rely on chemical and ...


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If we assume the computationalist point of view see e.g. here, then because it's hard to see any nontrivial computations being performed on the local level, you would not think that the galaxy can be a conscious entity in a local sense (i.e. that it generates a consciousness that is experiencing the local environment). But this leaves open the possibility ...


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Yes because the Earth moves with $v_{\rm Earth}=v_{\rm escape}/\sqrt{2}$ relative to (but not towards) the Sun. Here $v_{\rm escape}=\sqrt{2GM_{\odot}/1{\rm AU}}$ is the local escape speed from the Sun, while $v_{\rm Earth}=\sqrt{GM_{\odot}/1{\rm AU}}$ is the speed of the local circular orbit. An object at 1AU form the Sun and bound to the Sun cannot have ...



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