All Questions
8
questions
1
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1
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Describe the decrease in potential energy if two forces are acting on it one conservative which is greater than other applied by us in opposite dirn [closed]
So imagine this situation.
An object is experiencing two forces, one due to gravity in downward direction and other applied by us in upward direction such that our force is less than gravitational ...
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1
vote
1
answer
93
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Some questions regarding graviational potential energy and the concept of potential energy in general
Starting off, I first want to know the relation between work and potential energy.
$\Delta\mathbf U = - W $
How was this expression formulated?
Moving on,
My second doubt was in the derivation of the ...
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1
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2
answers
301
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Newton's Universal Law of Gravitation doubt
The Universal Law of Gravitation states that the module of the force, $F$ is
$$F = \frac{GmM}{r^2},$$
where $m$ and $M$ are the mass of the two objects and $r$ is the distance between the two objects....
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31
votes
4
answers
7k
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Why aren't the energy levels of the Earth quantized?
The Hamiltonian of the Earth in the gravity field of the Sun is the same as that of the electron in the hydrogen atom (besides some constants), so why are the energy levels of the Earth not quantized?...
- 1,523
-1
votes
2
answers
103
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Energy Creation Using Water, Generators, and a Pump
So a friend and I are arguing over an infinite energy idea that he had about using gravity, that is an almost infinite source of energy. Water to use to push a generator by dropping and hitting the ...
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4
votes
1
answer
2k
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Work performed by a stationary object in a gravitational field "on Earth" [duplicate]
I was thinking about this problem:
How much work is required to hold an object stationary in a gravitational field?
or:
How much energy is required to keep an object stationary in a ...
- 143
2
votes
0
answers
41
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Marvin the Martian vs. the Death Star: how much energy will they actually need to disintegrate the Earth? [duplicate]
Marvin the Martian vs. the Death Star: how much energy will they actually need to disintegrate the Earth?
According to a detailed analysis by Dave Typinski, Marvin the Martian’s Illudium Q-36 ...
- 360
9
votes
1
answer
614
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Marvin the Martian vs. the Death Star: how much energy will they actually need to disintegrate the Earth?
According to a detailed analysis by Dave Typinski, Marvin the Martian’s Illudium Q-36 Explosive Space Modulator will require $1.711 \cdot 10^{32}~\text{J}$ to shatter the Earth into a gravitationally ...
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