All Questions
Tagged with newtonian-gravity energy
125
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Can gravity be utilized to generate hydropower in a clean, repeatable fashion without rivers or lakes? [closed]
I came up with this idea today and am just wondering if it is feasible. It is much easier to communicate via images so I drew the attached image to convey it. The key concept is rolling a ball in ...
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6
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Why work done is needed when other physical quantities are available?
I have some question about work done. I understand the mathematical ways and examples which are floating all over on internet & books. But all these information not clearing the concepts of work ...
- 310
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Lagrangian potential for Newtonian gravity
In the Wikipedia site for Lagrangian (field theory) the Lagrangian density for Newtonian gravity is given by
$${\cal L}(\mathbf{x},t) = \frac{1}{2}\rho(\mathbf{x},t)\mathbf{v}^2 -\rho(\mathbf{x},t) \...
- 105
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In what direction is positive work done under a gravitational force, and what justifies the relation between work, potential and kinetic energy?
This has confused me for some time: if one integrates the gravitational force between two radii (let the motion of the particle always point toward the centre of mass of the other mass) from a radius ...
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4
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How do you calculate the energy required to hold a weight against gravity?
What is the energy required to hold a mass in place? To lift 1kg 1m at sea level I must use 9.8 J. but if I simply grab onto a 1 kg mass that is on a table and the table is removed. I am now using ...
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What is the Gravitational potential energy of two masses?
I'm having a bit of trouble understanding the gravitational potential energy. Suppose I have two masses $m$ and $M$ rotating around one another. Theres the gravitational force between them $F=-G\frac{...
- 147
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Work Done By Gravitational Force and Terminal Velocity
Using these two definitions of work:
Work = Force * Distance
Work = Change in a particle's kinetic energy
When a skydiver hits terminal velocity, their change in kinetic energy is basically fixed ...
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What is the total energy of a object if i throw it so far from the earth that it doesnt move towards earth? It seems there is energy loss
Let us assume that i throw a object A with velocity V_A. Then it reaches certain height H_A. At that point it has total energy which is equal to its potential energy and it comes down converting PE to ...
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Under which conditions do two moving bodies start orbiting each other around their center of mass?
If two bodies are close, both will get attracted to each other and collide. Under what conditions will the two bodies start revolving around their common center of mass? I understand that such bodies ...
- 415
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If Gravitational potential energy increase with height then why it is 0 at infinity?
Due to MGH relation, if we increase height then potential energy increases. Then why it is zero at infinity?
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Definition of a joule relative to gravitational PE
Why was it determined to calculate as 'pushing' an object (at the same height) over 1m instead of 'dropping' an object at 1 meter.
In other words, dropping a 1kg object at 1m would have 9.8J, but ...
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Why is gravitational potential energy $= mgh$? And how is it useful to us? [closed]
Who introduced the concept of gravitational potential energy?
Why do we need it to describe the physical world and how is it useful to us?
And from where does the formula $ U = mgh$ come from?
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Double counting potentials in $N$-Body Problem?
I suspect an error in my “Classical Dynamics” lecture notes but my lecturer doesn’t agree with me so I need your help!
We assume that in the $n$-body problem, the force between particle $i$ and $j$ ...
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What exactly is the energy source of tides?
Tides happen due to the gravitational interactions between the Earth and the Moon. We can say that the tides are pulled by the Moon's gravitational field and so it keeps on changing as it moves out of ...
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Is gravitational energy usable and could it be depleted?
Let's take for example a tidal stream generator. We know that tides are a consequence of the Moon gravity, we know that mass is connected with gravity, so is this mean that
(1) we use Gravitational ...
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