Questions tagged [tidal-effect]
The force on parts of an extended body in a non-uniform gravitational field, due to residual gravitational attraction between the overall effect on the body and the expected effect on the point in question. Tidal forces are most notably in large moons orbiting near their primaries.
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How do changes in energy distribution update the curvature of spacetime? [closed]
Let's give the name "gravitational signaling" to the information that affects changes in curvature. For example, the Moon draws changes in the curvature controlled by the Sun as it orbits ...
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Can fictitious forces always be described by gravity fields in General Relativity?
I was debating a geocentrist online who said that Einstein and a bunch of other physicists admitted a geocentric framework is valid. I replied that this was technically correct, but if you wanted to ...
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Will the moon ever proceed to lose its orbit and hit the earth?
Assume that the moon it orbiting the earth in a circular trajectory.
It will experience an acceleration directed towards the centre of the earth given by $\frac{GM}{R^2}$ where $G$ is the universal ...
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Why does the Earth move away from the Sun?
From the (Wikipedia's) definition of the astronomical unit $AU$, we have that it is defined as:
$AU=\sqrt[3]{\dfrac{GMD^2}{k^2}}$
Where $k\approx0.01720209895$ is Gauss' gravitational constant, $G$ is ...
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Can we design an experiment or an intuitive way to demonstrate tidal locking?
I was explaining the tidal locking phenomenon to a friend. First I started with the formation of solar system and how at the beginning the planets were actually like balls of magma-esque rocks. And ...
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Negative energy particle effect on observable object
A recent paper "Gravitational Pair Production and Black Hole Evaporation" (discussed in short here) says that any spacetime curvature would produce Hawking radiation, no need for event ...
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On the tidal heating of a moon. What is the second Love number?
Years ago it was asked here how to calculate the tidal heating of a moon orbiting another body with a simple equation. The answer is very detailed. They explain the equation, its shortcomings, the ...
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Correct explanation of tides [duplicate]
In the explanation of tides on earth there seem to be different versions for the second water bulge on the side opposite to the moon, while everybody seems to agree that the bulge on the moon side is ...
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Book recommendation for classical Newtonian gravity
I’m looking for a good textbook that covers Newtonian Gravity in detail (preferably advanced undergrad/grad level). One that covers important things like
Calculating trajectories of satellites around ...
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How does a gas giant planet hold it's spherical shape when it has tidally locked rotation in it's orbit around the Sun?
How does a gas giant planet hold its spherical shape when it has a tidally locked rotation in its orbit around its Sun? Wouldn't it fall apart without its gravitational pull from the rotation? How ...
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Would bending of spacetime make tides an invisible effect? [closed]
Similar to this question: How does general relativity explain tides?
But I’m specifically interested in if General Theory of Relativity would predict that bending spacetime means the water and land on ...
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Possible non-negligible physical effects that relate planetary/lunar geometry and seismic activity such as earthquakes?
Could any forces from the moon, the planets or the sun in orbit hypothetically influence seismic events on earth? And if yes how to approximately calculate and compare the magnitude of the forces?
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How can a grain of sand be "spaghettified" when nearing a black hole?
I have a hard time wrapping my head around this "spaghettification" process that apparently takes places when getting close to a black hole.
Gravity is proportional to the distance of the ...
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How big can a sphere of water in low earth orbit get?
Imagine that you have a large space station in low earth orbit, and inside that space station is a large sphere of water. How big can that sphere of water get before tidal forces overwhelm surface ...
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If two black holes orbit around each other should their tidal forces cause a shrinking of the closer parts of their event horizons?
I recently asked a question about the influence of external gravitational fields on the stability of the geometry of a part or all the event horizon of a black hole. I understood the answer in a ...
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Is tidal energy an infinite source of energy?
As tidal waves are caused due to gravitational force which acts infinitely until the presence of mass (the Moon) which make me think of an infinite source of energy. So what's wrong in here?
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What are the consequences of the tidal friction on the galaxy?
In the Earth-Moon system tidal-friction slows down the rotation, so does it do the same for the galaxy?
If not how come, and why it's different than on Earth?
If so can this slow-down be the reason ...
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How do tidal forces on incomplete geodesics determine extendability?
Why can we be sure that the manifold with the metric $(M,g)$ does not have a geodesically complete extension if it has an incomplete timelike geodesic along which the tidal force blows up? Does this ...
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Why is the time difference of equal tide states not 50 minute if one lunar day is 24 hour and 50 minutes?
I do understand that tidal forces are caused by de difference of gravitational force between both opposite points of the earth where a bulge is formed.
I do understand that a lunar day is ruffle 24 ...
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Can we find out if we are uniformly accelerating through flat spacetime by looking at non-accelerating clocks? [closed]
The equivalence principle states that locally you can't tell if you are accelerating through flat spacetime or are at rest in a uniform gravitational field.
Does this mean you can only tell the ...
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Do extended bodies in a gravity field fall slower or faster than point-like structures?
The weak equivalence principle states that all point-like particles fall along the same in a gravity field.
If a body is extended it experiences a tidal force which causes the bodie to elongate. If ...
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Will two passing bricks in empty space induce rotation in one another?
Two identical rectangular bricks with mass $m$ pass each other anti-parallel in empty space with a constant velocity $v$. Say the smallest distance between them is $s$. Assume the bricks to be aligned ...
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If the Earth and the Moon were smaller, would moon tides be more or less intense?
If the Earth and Moon were smaller (and everything on them too, but keeping the same average density and the same "relative" distances, I mean... the same proportions!), would the tides ...
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How can I determine the total energy and power provided by an ocean wave when it reaches shore?
When an ocean wave travels to the shoreline and breaks, how much energy is released? I did some research on finding out a formula to calculate how much energy is stored and then released by ocean ...
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Falling stones attached by a string
Suppose we have two stones, one "big" (A) and one "small" (B), the smaller one over the big one at the moment of free fall. Suppose also that a string of a certain length is ...
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How large can a sphere of water in low earth orbit get?
Imagine that er have a large space station in low earth orbit, and inside that space station is a large sphere of water.
How large can that sphere of water get before tidal forces overwhelm surface ...
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Wouldn't Millers planet be ripped to shreds by extreme tidal forces?
If you can survive lava-like temperatures there is another issue for the well-being of Miller's planet from Interstellar. Time passes on the planet 61000 times more slowly than for an observer far ...
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Could we be sucked up entirely by a micro black hole?
The hot question about being ripped apart in a black hole (no one can deny physics is boring!) got me thinking. If you cross the event horizon of a supermassive bkack hole, nothing noticeable will ...
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Why would black hole rip me apart?
According to my understanding of General Relativity, gravity is not a force and an observer which is falling freely under the influence of gravity should be considered inertial.
Now, I have come ...
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Is the gravitational tidal force equivalent to expanding space?
If you fall towards a black hole, the particles in front and the back of you, in the direction of the center, are accelerating away from you. So, seen from a freely frame, can we say that space is ...
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NASA's explanation on tidal acceleration
I've found an animation in NASA's website, illustrating tidal acceleration effect between the moon and earth.
It's the forth animation from the top in this page:
https://moon.nasa.gov/moon-in-motion/...
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How does Schwarzschild spacetime bend a free falling rigid body?
How does Schwarzschild space-time bend a free falling rigid body?
Will it be stretched or squeezed? How much it will be modified?
Can we find an effect of Lorentz contraction?
When will the assumption ...
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Tidal forces in daily situations: where to find it?
I'm trying to look for something that I'm not used to. My search is related to Tidal forces and the purpose is: making a qualitative explanation (@ High School level) of this phenomenon, using daily ...
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Tidal force in equivalence principle
The inertial frame of reference in a gravitational field is defined locally, but couldn't a sufficiently sensitive instrument detect tidal forces in the gravitational field and thus make the frame in ...
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Are there tidal forces between the solar system and the galactic centre?
Tidal forces are experienced within a system moving in free fall around a bigger object because of the different strength of gravity over the system. The difference can be calculated between the far ...
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Could a moon keep orbiting a planet forever?
Our Moon orbits the Earth further away each year due to the tidal forces but could there be a moon orbiting a planet where somehow keeps going further away by the tidal forces but its attracted again ...
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Smallest pool to form tidal wave
Tidal waves form in the ocean, while not in my swimming pool.
I wonder what's the smallest swimming pool is like to form tidal waves.
It's true that tidal wave always exists, let's assume we want a ...
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Gravity contradicting conservation of energy? [duplicate]
If we could utilize gravitational force to create energy, could gravity, being unlimited, generate unlimited energy?
Consider electricity generation from tides. Since tides are due to gravity, aren't ...
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Roche limit and satellites orbiting each other
Does the Roche limit apply also to two satellites orbiting each other or only to individual satellites held together by gravity?
For example, I have a tungsten little ball (10 cm in diameter) around ...
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More volume with more mass?
Regarding to the Schwarzschild solution, is there more volume with more mass?
Lets take for example a space shuttle (spheric for simplicity) in an stationary orbit at the position $r_1$.
The black ...
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Einstein equivalence principle
I know that there are two different formulations of Einstein's equivalence principle: the weak version says that the inertial and gravitational mass are equal. On the other hand the strong version ...
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Does a uniform gravitational field exist? Is there any acceleration in a uniform gravity field?
This question arose in the Space Exploration forum, by non-physicists, so it likely sounds naïve. The question involved the plausibility of using a very strong gravitational field to accelerate an ...
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Tidal forces mathematics
Let's calculate the difference in force, $\Delta F$, experienced by
the rocks. Because $\Delta r$ is very small compared to $r$,
$$\Delta F = F_{\text{out}} - F_{\text{in}} \approx\frac{dF}{dr}\Delta ...
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Could a set of rogue double planets (binary planets) be habitable due to tidal forces?
I want to write a story about rogue double planets and was wondering if it's possible to have a double planet where either both or one of the planets are habitable due to tidal forces even if the ...
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How does general relativity explain tides?
How general relativity explains tides using spacetime curvature? and if the full moon can affect water, inside the international space station did the ever observe small things like water droplets ...
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Derivation of Roche Limit
In calculation of the Roche limit between the two celestial body, tidal force on small mass $u$, $F_t$ is expressed approximately as $$F_t=\frac{2GMur}{d^3}$$ While deriving $F_t$, what's the reason ...
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Earth, Moon, gravitatioal pull
Does the gravitational pull that causes tides, also affect the Earth's land mass. Does it affect the atoms, molecules, is there a slight bulge to the actual Earth / Land itself?
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Weight dependency on the location on Earth relative to Sun
In this post a theoretical physicist says that one will weigh less at the point on the Earth closest to the Sun due to the Sun's gravity, which makes sense to me. But he also says that one will weigh ...
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Will the increasing distance between Moon and Earth result in speeding up or slowing down of Earth's rotation period?
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The Moon tidally brakes Earth's rotation, and as a result distances itself away from Earth as a result of conservation of total angular momentum*. Certainly, tidal braking slows the rotation ...
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Can an observer in a double tidal locked system figure out it is orbiting?
Tidal locking, when the spin rate of a body matches the orbital rate so that it always faces the other body with the same side, usually occurs for just one of the bodies in orbit. However, there are ...
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