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incompressible: not able to be compressed. compressible: In thermodynamics and fluid mechanics, compressibility is a measure of the relative volume change of a fluid or solid as a response to a pressure (or mean stress) change. So water does not change its volume. The same volume of water can take many shapes. When no other gravitational force except ...


9

I think you have started from a picture of the tides making water go up and down that is a natural picture to have, but it is wrong: they don't. If that picture were right, you ought to be able to measure the tides just by digging a deep well. What happens is that the influence of the moon (and sun) changes the shape of what is meant by "level" - ...


3

Half. The escape velocity for an object at a distance $D$ from an object of mass $M$ is $\sqrt{2GM/D}$. The circular orbital velocity (the Moon is on an orbit that's close enough to circular that I'll just assume this) at the same distance is $\sqrt{GM/D}$. Setting the escape velocity from the Earth with it's new reduced mass $M_{\rm new}$ equal to the ...


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@CuriousOne is approximately right. Others have thought of it, the url below is a paper from one who concludes with slightly more careful calculations (but still relatively straightforward) that the most one could get in terms of a continuous power from it is 50 MW, and typically a lot less. 50 MW is 5% of a large power plant. http://www.electrostatics.org/...


2

Lots of these answers expect you to know a lot about the way gravity works. From these, I've managed to come to the answer, and in this post I'll try to dumb it down to my level. To start with, I'd like you to imagine a tray, or an empty biscuit tin - something with a flat base and rims. Now imagine you pour water into this tray (feel free to actually pour ...


2

Tides are the resultant of attraction from earth (major effect), moon (secondary) and sun. Other planets'influence can be neglected. The position of the moon (and of the sun) cause a slight variation in equipotential surfaces on the earth, and the water as a liquid naturally tends to follow an equipotential surface. Of course those variations are by ...


1

Assuming that we are making a certain amount of the earth's mass disappear instantly somehow, doing this will decrease the escape velocity of the earth. The moon is already moving at its orbital velocity in an orbit centered on the current center of mass of the earth-moon system. If we took away so much mass (instantaneously, somehow) that the escape ...


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There is a slight effect on the lift requirement for an aircraft. A "stationary" object on the equator is actually traveling in a circle, at one earth-circumference per sidereal day velocity. That lessens its apparent weight because it is accelerating toward the center of the earth (centripetal acceleration). The effective gravitational constant (g minus ...


1

Phenomena is called Cold Welding The reason for this unexpected behavior is that when the atoms in contact are all of the same kind, there is no way for the atoms to “know” that they are in different pieces of copper. When there are other atoms, in the oxides and greases and more complicated thin surface layers of contaminants in between, the ...


1

First of all, let me correct a misconception. According to your question, your understanding of the structure of the Earth is that there's a solid crust of 5 to 50 km and below it there is liquid. This is not correct. The Earth is mostly solid. It's solid almost all the way down: you can drill down 3000 km without seeing any liquid at all. The liquid you do ...



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