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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Do tidal forces create atmospheric jet streams?

Earth's large-scale wind patterns (a.k.a. jet streams) are generally attributed to "differential heating" by the sun. But the large-scale patterns in Earth's oceans (a.k.a. tides and tidal ...
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Struggling to prove Newton's Law of Gravitation starting from smaller bodies

I have seen at least four different posts in this website in which the OP asks for a proof of Newton's Law of Gravitation (often without stating from which axioms the proof should start) all of which ...
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How does tidal locking work if planets are almost perfect spheres?

I guess this question has more to do with orders of magnitude than actual theory but as I understand, planets like mercury are almost perfect spheres with very minor deviations. For instance, ...
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Do black holes rip apart even atoms and protons and neutrons?

I am aware that black holes rip apart objects because of spaghettification. What about atoms and protons and neutrons? Do they get ripped apart too? But, in the case of protons and neutrons, wouldn't ...
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How are relativistic tidal forces different from their Newtonian counterparts?

Conceptually, the tidal effects of Newtonian gravity differ drastically from that of general relativity. In Newtonian gravity, the effect is due to the change in gravitational force across a certain ...
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How much of the Tidal Energy can be attributed to the Sun?

I'm been researching this question but haven't been able to find a conclusive answer. As I understand it, there are two forms of tidal energy: tidal potential energy and tidal current energy. Tidal ...
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Spaghettification - Singularity is just energy?

So... as matter falls into a black hole the tidal forces tend toward infinity as you get closer to the singularity. These tidal forces overcome the bonds between atoms, then the bonds between nucleons ...
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Do you really die if spaghettified by a back hole?

Considering gravity acts by stretching spacetime and all forces (EM, nuclear etc...) are relative to spacetime, can we then consider that regardless of how stretched you are to an observer outside the ...
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Does a experiment measured in free fall here on earth and inside a black hole gives the same result?

According to Einstein equivalence principle observer in free fall measure the same thing in experiment made in their laboratory frame. Let us take for example the probability $P$ of an hydrogen atom (...
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$\hat{\phi}$ tidal acceleration of a black hole

For Schwarzchild geometry I've calculated the tidal acceleration in the $\hat{\phi}$ direction for two particles initially at rest separated by $\Delta \phi.$ $$a^a = -R_{cbd}{}^aX^b T^c T^d$$ Where $...
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Does bottle water rise a little bit on full moon days?

High tides and low tides are caused by the Moon. The Moon's gravitational pull generates something called the tidal force. The tidal force causes Earth—and its water—to bulge out on the side closest ...
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Do steep, 1200 meter high water waves (“rogue waves”), due to tidal effects, exist?

In a comment on another question, I saw the movie Interstellar mentioned. And I immediately thought about the scene in which some members of the discovery team had landed on a planet circling the ...
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Experimental confirmation of tidal forces in the gravitational field

Are there any experimental confirmations of the tidal forces in a gravitational field? Specifically I am interested in the following effect: consider two objects of mass $m$ with relative distance $x$ ...
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Problem in steps deriving tidal forces

I am looking at this paper, discribing tidal forces. I cannot get my head around how they got from $(4.2)$ to $(4.3)$: $$r_1^{-1}=\frac{1}{R}\left[1-2\frac{r}{R}\cos\psi+\left(\frac{r}{R}\right)^2\...
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If I jump into a black hole, will I see myself passing event horizon? [closed]

Given a black hole with mass of the Milky Way (1.6x10^42 kg), I built a frame that 1 m above the event horizon. I am jumping from this frame my legs down (since I am afraid to dive into a dangerous ...
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Earth's atmosphere as an oscillator

I have read that earth's atmosphere is an oscillator because it is effectively revolving about the earth. However, this is an example of forced oscillations because the moon also effect it with it's ...
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Tidal forces of radial geodesics in Schwarzschild spacetime [closed]

Let me start with the questions I have: Since infinite tidal forces at the event horizon are meaningless, is this yet again a result of the choice of coordinates? What exactly do we call the tidal ...
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Can you explain tides in our water bodies with respect to Theory of General Relativity and spacetime curvature?

We read everywhere that Moon's "gravitational pull" causes tidal waves. Is there any explanation of this "gravitational pull" in terms of General Relativity and curvature of ...
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The gravity-acceleration equivalence principle doesn't seem like exact equivalence. Is there something I'm missing?

Suppose I'm trapped in a box, and the box is $3\ \mathrm{m} \times 3\ \mathrm{m} \times 3\ \mathrm{m}$. I designate one vertex to be $(x,y,z)=(0,0,0)$ and the opposite one as $(x,y,z)=(3,3,3)$. I'm ...
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The role of the Sun in spring and neap tides

I am trying to understand how the Sun affects tides on the Earth's oceans and seas. It is quite clear that when the Moon is in the first and in the third quarter, the Sun's and the Moon's ...
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Earth's unimpeded rotation for billions of years [duplicate]

My nephew (7th grade) has stumped me with this question. If I spin a top, it eventually stops, because of friction, air resistance etc. How come the Earth has been spinning non-stop for 4.5 Billion ...
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Tidal effect on interferometry

Interferometry relies on the change in the phase of two orthogonal light beams reflected back to the source point. Assume there is an interferometer at the equator, one mirror is planted 1 mile due ...
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Schwarzschild radius violation?

I have a puzzling question concerning the crossing of the Schwarzschild boundary. If a person (lets say in some large robust spaceship) flys quickly between 2 super-massive rotating black holes within ...
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In the difference between the sun and moon's tidal effects on earth, is density or distance a larger factor?

This question is inspired by the (now looking at it, improper use of, my bad) comments section here in Physics SE. I'm not sure I could explain better than our short discussion does below: No, the ...
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If you drop a slinky into a black hole, does it stretch out? [closed]

If so, where does the energy come from?
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Tidal locking and heat dissipation

I need to know that how does one measure (approximate) the energy loss of a planet or satellite during the whole tidal locking process? Where do I find this topic to study?
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Why do tidal forces exist in black holes?

If a person (free)falls into a black hole at some point or the other, he will be stretches by a 'force differential' between the two ends of his body. This is the process of spaghettification. But, ...
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Are there any effect of Sun to the tide? [duplicate]

The Earth is rotating for the Sun's gravitational field. Like a free falling object Earth should feel zero gravity to the Sun. So why there are effect of Sun to the tide?
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Does an observer inside of an accelerated frame experience tidal force?

Thanks to Andrew Steane and Pulsar in this topic I understood that in a frame with constant proper acceleration, each hyperbola in $T-X$ diagram demonstrates a constant position while each line ...
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How much the Earth atmosphere oscillates due to Moon tidal force and does this produces winds?

As there is the tidal force of the Moon exerted on the Ocean water I supose there must be some force acting to the Earth's atmosphere. So when the atmosphere starts falling down as the Moon is ...
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How to calculate the bulge in a swimming pool surface caused by a local point mass?

Imagine a swimming pool of an arbitrary width, small on a planetary scale. At a height above its usual surface, a superdense mass is suspended. How do I calculate the distortion in the surface of the ...
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Gravitational field

We know that for a gravitational field calculation $E = \frac{GM}{r^2}$ we consider a test mass, i.e. a small mass, but how does a big mass actually affect the gravitational field.
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Effect of Earth's Rotation on Time [closed]

According to Wikipedia: Earth's rotation is slowing slightly with time; thus, a day was shorter in the past. This is due to the tidal effects the Moon has on Earth's rotation. Atomic clocks show that ...
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What is the main reason for the locality of Einstein's equivalence principle?

Einstein's equivalence principle (EEP) states: "Locally, a free-fall frame in a gravitational field is equivalent to an inertial frame in space in the absence of a gravitational field". ...
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Can tidal locking increase rotational kinetic energy? Where does the energy come from then?

I was thinking about the explanation for how the Moon gets tidally locked with the Earth. We are working in the non-rotating reference frame of the Earth, and assume it is inertial (to an approximate ...
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How does spaghettification work in general relativity?

Imagine a neutron star is being consumed by a black hole, so I think matter from the star is being stretched as it follows the curvature of the spacetime around the black hole. If that is the case ...
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Does tidal force continue to increase as a man falls into a black hole?

Small black holes have collosal tidal forces at their event horizons. But there are black holes large enough where a man can cross the event horizon without being ripped apart. But does the tidal ...
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Why do tidal waves appear so suddenly in some rivers?

As tide approaches in lower part of some rivers (e.g. Ganges), a several feet high tidal wave enters from the sea against the flow of the river (making a great noise), and the water level suddenly ...
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What happens if you spin a coin in space?

Will the coin spin forever or will it be de-accelerated by the gravitational force?
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How much does $g$ vary according to the position of the moon?

The gravity of the earth or more specifically the gravitational acceleration, $g$, is the acceleration objects with mass experience toward the earth due to gravity. How much does this vary according ...
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Can geodesic deviation in free fall sometimes be indistinguishable from mutual gravitation?

Suppose you are in radial free fall at some point outside the event horizon of a Schwarzchild metric. The strong equivalence principle implies that locally you would be unable to discern whether you ...
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How strong are the tides raised by Io on Jupiter relative to the ones raised by the Moon on Earth?

There seems to be 2 ways of calculating tidal forces that are contradictory. Either: By calculating the difference of Io's gravitational acceleration on a point on Jupiter's near side and the ...
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If Saturn's rings cannot coalesce into a moon because of tidal forces, then how are shepherd moons able to exist?

From Wikipedia: In celestial mechanics, the Roche limit, also called Roche radius, is the distance within which a celestial body, held together only by its own force of gravity, will disintegrate due ...
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Do all tidal effects vanish in the limit where GR reduces to SR?

I'm an amateur studying General Relativity (GR). A basic question on which I'm still unclear is the sense in which GR reduces to Special Relativity (SR) in the limit. I understand that the laws of SR ...
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Angular momentum of the earth

We know the tidal waves are decreasing the spin rate of the earth which causes the days to longer, so as the angular momentum of the earth decreases it means it rotational kinetic energy also ...
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What (and if) is the difference in the form of the tidal bulges on the Earth with a smooth surface and the rough surface as it actually is?

It's clear that on a smooth surface of a massive sphere $M$, covered with water, two bulges of water appear when it's rotating in sync with a satellite (a massive sphere with a substantially smaller ...
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How do tidal forces change gravitational waves

If there is a binary of two neutron stars, they are going to be deformed because of the tidal forces. I suppose that it will cause a change in the movement of the stars and that will cause a change in ...
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Why do I have an extra factor of 3 for self-gravity?

So, I'm trying to calculate the "acceleration" (force / mass) on a spherical object of mass $M$ and radius $R$ due to its own gravity that holds it together. So, here is what I figured. The "...
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Harvesting energy from Moon's orbit without water [closed]

We use the gravitational interaction between the Sun, Moon, and Earth to harvest energy from the motion of the oceans, the tidal "bulge", along coastlines. This uses the changing sea level to ...
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Is a planet hot inside because it is still hot from beginning, or continuously heated? [duplicate]

If a planet emerges from multiple colliding pieces, that causes its material heat up. Later, an existing planet is continuously heated by radioactive decay, tidal forces and other effects. But are ...

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