Gravitational energy or gravitational potential energy is the potential energy a massive object has in relation to another massive object due to gravity. It is the potential energy associated with the gravitational field, which is released (converted into kinetic energy) when the objects fall towards each other. Gravitational potential energy increases when two objects are brought further apart.
For two pairwise interacting point particles, the gravitational potential energy
U
{\displaystyle U}
is given by
U
=
−
G
M
m
R
,
{\displaystyle U=-{\frac {GMm}{R}},}
where
M
{\displaystyle M}
and
m
{\displaystyle m}
are the masses of the two particles,
R
{\displaystyle R}
is the distance between them, and
G
{\displaystyle G}
is the gravitational constant.Close to the Earth's surface, the gravitational field is approximately constant, and the gravitational potential energy of an object reduces to
U
=
m
g
h
{\displaystyle U=mgh}
where
m
{\displaystyle m}
is the object's mass,
g
=
G
M
E
/
R
E
2
{\displaystyle g=GM_{\text{E}}/R_{\text{E}}^{2}}
is the gravity of Earth, and
h
{\displaystyle h}
is the height of the object's center of mass above a chosen reference level.
Electrons flowing through a resistor are dissipating electrical energy. The electrical energy is transported from the battery to the electrons along the curved field lines of the Poynting vector. It seems like a meaningful idea that electrical energy necessarily travels from the source to the...
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First of all, I did not major in Physics, but I did pass GCE with A. (This is to make a point, not to boast.)
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For centuries we have been using the gravitational potential energy of water courses by building watermills and dams with hydroelectric plants. The weather does the job of bringing the water back 'upstairs' for free so conceptually that's a wonderful energy source. The problem is (I guess) that...
Is the height in the formula the vertical distance from the bottom to the center of gravity of object, or is it just the vertical distance from the bottom to the very top of the object.
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If there is a sphere with mass m and radius r and placed at height h, what is its potential...
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In nature, all forces have a limited value, i.e, their effect is reduced if many objects are influenced by that force. Example, the magnetic force experienced by a single iron nail (in a magnetic field) is greater than that of 2 iron nails in the same field.
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We know that gravitational energy is negative (zero energy universe theory). If the mediator particles (bosons) of the gravitational interaction are gravitons, then the energy of the gravitons would be negative?
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How do you derive the equation for gravitational force from the eqauation for potential gravitational energy: e=-Gm/x? For me it seems as though you take the derivative and that would work, but i don't understand why it does?
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I am 65 kg and eat a 500 Calorie lunch and go hiking up a mountain afterwards. Assuming that chemical energy is converted to gravitational potential energy with 50% efficiency, approximately how many miles up the mountain can I go before I need my dinner?
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In those two links it is written that gravitational energy does not exist.
http://arxiv.org/abs/0908.3322
http://fqxi.org/community/forum/topic/1371
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A ball is thrown up in the air and reaches a height of 2.2m assuming that all the energy is gravitational what speed was the ball thrown at.
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0.5kx^2 (final) +...
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Welcome to the Australian Physics course! I have to analyse the effects of changes on gravitational energy and radiation from the Sun on a manned spaceflight to Mars. I doubt my abilities to solve simple problems, however, so I now turn to the vast collective of the...
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The Attempt at a...
Hello, the concept of potential gravitational energy seems very confusing to me, and it leads me to several questions, and I was wondering if some of you could explain this energy conceptually to me perhaps based with these questions as guidelines.
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I chanced upon an argument in Misner, Thorne and Wheeler to the effect that the energy/momentum of the gravitational field cannot classically be localised. Basic idea: you can make the Christoffel symbols vanish at any point, and hence the gravitational field at that point will vanish, taking...
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