All Questions
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How to calculate the total energy of a planet at rest?
Let's just say we have the Earth-Moon system isolated in space, with Earth at rest, and the moon orbiting it.
How can we calculate the total energy of Earth in such a case (Kinetic energy would be ...
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3
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286
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Energy of a planet moving around the Sun
In chapter 13 of volume 1 of The Feynman Lectures, Feynman is discussing how the work done in going around any path in a gravitational field is zero. Here's the link: http://www.feynmanlectures....
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Why doesn't gravitational potential energy cancel out?
If you have 2 stars of mass $M$ and seperated by a distance $2R$, and a planet of mass $m$ is equidistant between them, the potential energy of the planet is given by:
$$E_p = \frac{-2GMm}{R}$$
This ...
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1
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1
answer
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Energy diagram of a planet with fixed mechanical energy
Consider the following energy diagram for the motion of a planet about a star.
The centrifugal potential curve can be represented once I fixed the angular momentum $\vec{L}$ of the planet. To fix the ...
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Minimum energy required to remove the satellite from its orbit to infinity?
My book says that minimum energy required to remove the satellite from its orbit is equal to its total energy (K.E+P.E). But shouldn't it equal to only the potential energy difference of satellite in ...
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What is exactly gravitational potential energy and explain P.E. $= -GMm/r$? [duplicate]
I was studying gravity and I came to know about $P.E.= -\frac{GMm}{r}$ which is derived by $GMm(\frac{1}{\infty} - \frac{1}{r})$ which the work done by the body to displace it from infinity to $r$. ...
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Is there anything interesting about an n-body system whose potential energy is constant?
I am curious about a system of gravitating bodies with particular characteristics. Before describing the characteristics of the system, let me say what I want to know about it:
Can this be a ...
- 1,517
6
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2
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Gravitational potential outside Lagrangian points or Lagrange points
The diagram in Why are L4 and L5 lagrangian points stable? shows that the gravitational potential decreases outside the ring of Lagrange points — this image shows it even more clearly:
If I ...
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9
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Why are $L_4$ and $L_5$ lagrangian points stable?
This diagram from wikipedia shows the gravitational potential energy of the sun-earth two body system, and demonstrates clearly the semi-stability of the $L_1$, $L_2$, and $L_3$ lagrangian points. The ...
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