Questions tagged [gravity]
Gravity is an attractive force that affects and is affected by all mass and - in general relativity - energy, pressure, and stress. Prefer newtonian-gravity or general-relativity if sensible.
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Two orbiting planets in perpendicular planes
Inspired by this question. Can a 3 body problem, starting with two planets orbiting a larger one (so massive it may be taken to stand still) in perpendicular planes, be stable?
Is there known an ...
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Forces in a Pendulum
Help me visualise the forces found in a pendulum. I know weight can be decomposed into $F_x$ and $F_y$.
Centripetal force, acceleration and velocity are three words that I'm confused. Centripetal ...
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Strongest force in nature
Possible Duplicate:
What does it mean to say “Gravity is the weakest of the forces”?
It is said nuclear force is the strongest force in nature..
But it is not true near a black hole ...
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If energy is only defined up to a constant, can we really claim that ground state energy has an absolute value?
Sorry if this is really naive, but we learned in Newtonian physics that the total energy of a system is only defined up to an additive constant, since you can always add a constant to the potential ...
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How do horseshoe orbits work?
An asteroid was recently discovered that is in a horseshoe orbit with respect to the earth. Is there an intuitive explanation for these orbits? It seems that the earth acts as a repulsive force where ...
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Maximum time difference between clocks in a gravity field
From Surely you must be joking, Mr Feynman.
You blast off in a rocket which has a
clock on board, and there's a clock on
the ground. The idea is that you have
to be back when the clock on the
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Dig a hole to the other side of the Earth [duplicate]
Possible Duplicate:
If it was possible to dig a hole that went from one side of the earth to the other…
This question may not be suitable here and it could be closed in seconds but I wanna ...
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Has somebody ever tried to measure the gravity oscillations of nearby rotating masses?
I'd like to extend this question:
Are Newton's gravity waves detectable by a laser interferometer?
but with some changes.
Has somebody ever tried to measure the gravity oscillations nearby (&...
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Are Newton's gravity waves detectable by a laser interferometer?
Newton's theory of gravity supports "gravity waves" in that moving objects cause changing gravitational fields. For example, two bodies rotating around their center of mass will have a stronger ...
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Gravity and Planetary Differentiation
During solar system formation, many bodies achieved hydrostatic equilibrium, a spherical shape where their self gravitational force was balanced by internal pressure. Many also achieved ...
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How does the curvature of spacetime induce gravitational attraction?
I don't know how to ask this more clearly than in the title.
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Does the curvature of spacetime theory assume gravity?
Whenever I read about the curvature of spacetime as an explanation for gravity, I see pictures of a sheet (spacetime) with various masses indenting the sheet to form "gravity wells." Objects ...
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Mass Needed to Clear an Orbital Neighborhood
In 2006 the IAU deemed that Pluto was no longer a planet because it fails to "clear" the neighborhood around its Kuiper Belt orbit. Presumably, this is because Pluto (1.305E22 kg) has insufficient ...
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Gravity and the Standard Model
Gravity is ignored in the SM. The proton rest mass is ~0.938 GeV/$c^2$. LHC protons will move with 7 TeV energy, presumably with a relativistic mass about 7,450 times rest mass. A cosmic ray with the ...
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Where's earths death bulge, destroying everything in it's path?
I was watching a BBC documentary on space last night. It was talking about gravity, and it said that the reason we only ever see one side of the moon, is because the earths gravity is strong enough ...
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