Questions tagged [earth]
Earth is the planet on which we live, the 3rd planet from the Sun. Questions using this tag should be about Earth the planet and not Earth-like planets nor earth, as in dirt or soil.
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If Earth slows down its rotation due to tides will this be diminished by the friction between its different layers as they cool down?
If we suppose that planets act simmilarly to galaxies or planetary systems which inner parts move faster than the outer will then the possibly faster inner layers of Earth speed up the surface by ...
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Did barycenter of earth-moon system produce time-dilation
Did the barycenter inertial mass can produce time dilation if it's inside the internal big bodies such as earth
Can the time-dilation be calculated inside inertial frame of reference using meridian ...
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Would everyone die? [duplicate]
When you open the door of your spaceship, the oxygen disappears from the ship.
So if I put a very very long tube from the Earth to space,
would all the oxygen from the Earth automatically aspire into ...
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What are the sources of error in the formula I derived to estimate sunrise and sunset times, and how can I improve its accuracy? [closed]
I derived the following formula to estimate sunrise and sunset times:
$$ t=\pm\cos^{-1}\frac{\sin\theta-\sin L_{loc}\sin L_{sun}}{\cos L_{loc}\cos L_{sun}} $$
$L_{loc}$ is the local latitude
$L_{sun}$...
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How much energy from the Sun could we get if we use Jupiter as a gravitational or atmospheric lens?
How much energy (watts) from sunlight could arrive to the focal point if we use Jupiter as a gravitational lens? and if we use it as an atmospheric lens by using refraction?
How far the focal point ...
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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 the inner core of the Earth drop?
If standing on earth, I experience the planet's gravity. Rain drops are accelerated to move toward its centre and reach the crust. These attractions are mutual. This contrasts to e.g., the ISS with ...
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Can we stop the Earth from spinning?
When we walk on the ground, we push the ground backward and hence the ground pushes us forward and we change our position. The effect of our force on the Earth is very minute (literally negligible) ...
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What will pole reversal cause to modern world and civilization?
I don't think it's just a matter of reorienting maps and recalibrating compasses.
In any case, how long does a inversion last? hours, days, weeks, years? If it lasts days or more.... would Sun fry ...
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THE LINE OFTHE MOONLIGHT IS NOT STRAIGHT ANYMORE [closed]
I am from the USA, just a retired soldier who looks at the sky a lot. This morning 26 SEP 2020 at 1am, the Moon was approximately a quarter Moon. It was bright, the line/shadow on the moon was not ...
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Is there an equation for the gravity of Earth that accounts for a comprehensive set of variables?
(e.g., longitude/latitude, elevation, and Earth’s mass and rotational speed)
I know a couple of approximations for the gravity due to Earth’s mass. The usual one I’ve been given is $g \approx 9.8 \, \...
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Earth doesn't have seafloor craters. Does it mean water has been on Earth since long time before in the past?
Is it true that Earth didn't get its water by cometes impacts as there are no subocean craters so it seems water acted as a comete bumper long before in the past?
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Can centrifugal force inside Earth's outer core overcome gravity?
As the gravitational field inside Earth outer core is relatively weak can the angular momentum of Earth's outer core be high enough to cause lighter elements or compounds being deposited in Earth's ...
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1answer
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Why the inner core of planet Earth is not composed of the densest materials?
I read on various sources the inner core of our planet is said to be mostly composed of a iron-nickel alloy, plus some lighter elements like silicon. On the other hand, I know that in general lighter ...
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How much time dilation are we experiencing here on Earth? [duplicate]
We experience time dilation from speed and gravity, but we are in more than just the Earth's gravity field, but also the sun's and the galaxy's gravity field and we are both spinning at 1,670 km/h, ...
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Doesn't Increase of Potential Temperature with Height contradict Adiabatic Nature of Processes within Troposphere?
According to my education as a sailplane pilot our troposphere is in good approximation subject to adiabatic processes.
Using adiabatic equations of (nearly ideal) ...
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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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Would the change of Earth's speed of rotation induce a magnetic attraction between two charged particles?
When two negatively charged particles are standing still regarding the ground I assume there will be only an electric repulsion between them with no any magnetic interaction. But let say we can speed ...
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Problem on Angle of declination [closed]
There was a problem in my book that read- A magnet is pointing towards geographic north at a place where the horizontal component of the Earth's magnetic field is 40 microtesla. Magnetic dipole ...
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Is ECI a pseudo-inertial frame?
The Python poliastro package documentation states that, when propagating from position and velocity vectors, the orbit's reference frame will be "one pseudo-...
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Does magnetic field exist throughout space?
My question is quite subjective and I could not find a suitable explanation to whether there is a magnetic field in space beyond earth .I read one of the article stating
Interstellar dust clouds have ...
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1answer
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How big (in meters) could the difference be between ECI and ECEF coordinates at midnight UTC?
Is the only difference due to leap seconds, etc. or other differences between UTC and updated forms of universal time, such as UT1? In other words, are all earth-centered inertial (ECI) coordinate ...
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What would be the increase of gravity if we create a new world slightly bigger than the earth? [closed]
I need to know what would happen if I increased the earth's size by a small percentage to make a fictional world similar to earth. So my thought process is this: My thinking started with increasing ...
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How would a rope around Earth fall? [duplicate]
I have searched and saw a similar question but i dont know if it's exactly the same.
If I had a rope around earth, let's say a few meters above (and supposing a flat surface, and suddenly dropped it ...
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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 does not accelerate?
According to special (& galilean) relativity, there is no difference between constant movement or not moving at all but it is possible to detect acceleration and rotation is acceleration.
The ...
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Radius of Circular orbit of a Satellite around Earth always constant (if Space was a perfect vacuum) WHY?
The way I see it:
Assuming space is a perfect vacuum, a satellite should stay in circular orbit with CONSTANT RADIUS around earth forever but I think the radius should gradually decrease for the ...
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3answers
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How is the Earth an approximate inertial frame? How can one validate this?
I have always been confused by the idea of Earth being an approximately inertial frame as the speed at which it rotates is so high. Everywhere vaguely it is referred through calculation it can be seen ...
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Is the delta-V value from Low Earth Orbit (LEO) to Low Mars Orbit (LMO) equal to the delta-V value from LMO to LEO at same altitudes?
Radius of Earth = 6378km
Radius of Mars = 3397km
Sun-Earth distance = 149597600km (1 AU)
Sun-Mars distance = 227986742km (1.524 AU)
LEO = LMO = 500km
NOTE: Assuming Earth and Mars revolve the Sun in ...
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1answer
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Magnetic field in a Tangent Galvanometer
I was reading about the tangent galvanometer online. I came across a youtube video : https://www.youtube.com/watch?v=wIuAnP9xfxw .
It said that the field produced by the circular coil of the ...
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1answer
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Entropy of photons in the Sun / Earth system - Do infrared photons have higher entropy than ultraviolet/visible photons?
The entropy of a photon gas in equilibrium (emitting e.g., black-body radiation; BB) is
$S \propto V \cdot T^3$
where $V$ is the volume and $T$ is the temperature of the gas [see https://en.wikipedia....
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Why do we say that the torque on Earth due to Sun is zero?
Let's assume, the mass of Earth = $M$, the radius of Earth = $r$, the moment of inertia due to revolution of Earth = $I$, angular momentum due to the revolution = $L$, distance between the center of ...
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1answer
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Parallel Stripes and the classic globe confirmation experiment [closed]
I have been taking time this summer to try and understand what "reasons" some flat earthers offer for their beliefs for a "science and the public" class. One of the oldest and most ...
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2answers
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Calculate Earth angular speed [closed]
How may I calculate Earth's angular speed at specific point (The green dot for example)?
Note: I know that angular speed $= \dfrac{2\pi}{T}$ But how may I found $T$ in this case?
I found too that $R_{\...
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Why don't hovercrafts move West relative to the Earth [duplicate]
Suppose that there is a hovercraft floating a few centimetres above the Earth's surface. As it is disconnected from the Earth, which is spinning from West to East, shouldn't it appear to move East to ...
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If hypothetically we manage to transfer electrons inside the earth enough to a create a considerable amount of charge inside earth.What would happen?
We know that earth is neutral in charge. It has zero potential and this is the reason why electrons move towards earth while lightning or earthing.
If we manage to transfer a considerable amount of ...
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Why does the trend of gravitational field of Earth is like this ( the graph below)? [duplicate]
I think that, since Earth is spherical, the amount of mass in the upper half of Earth should be the same as the second half, therefore, if the strength of gravitational field increase linearly from ...
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Thought experiment: Could the Earth be cooled by pumping refrigerant?
Possibility of Using a Refrigerator to Cool the Earth
I understand that the Earth as a whole cannot be cooled directly by radiating energy away for theoretical reasons. Waste heat has low entropy; ...
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Does Earth's Gravitational pull increase with time?
Gravitational field depends on mass ($g = \frac{GM}{r^2}$) and every year many outside cosmic objects like asteroids or tiny object are hitting earth. So I think may be in a very microscopic amount ...
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What happens if I place myself on a land pole?
What happens if I place myself in the center of one of the Earth's poles?
Could I see how the earth revolves around me?
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Is the gravitational force for an object on the surface of earth always pointed to the center?
I thought it would be so because the mass inside the earth would attract us however they would be at a larger distance than masses on the surface of the earth.
For example, consider having a tall ...
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Ptolemy physic astronomy
in Claudius Ptolemy physic of universe did earth is sphere or Flat ؟
did earth orbit around itself or it is stable?
why he think star have impact on human life ?
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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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Does Acceleration due to Gravity take into consideration the centrifugal acceleration due to Earth's spin?
Is the gravitational acceleration we consider only the attraction due to the Earth's gravity or is it that of gravity plus the attraction due to Earth spinning?
We know that earth produces an ...
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where do the gases such as hydrogen and helium end up after leaving the earths atmosphere?
I've heard that gases like hydrogen and helium leak out of the earth's gravity a little by little.
but where are they going? where do they end up after leaving earth's pull?
would the sun pull them ...
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Cumulative Sun's radiation pressure exerts on Earth's surface
I have some discrepancies in what is in "Optics" (E. Hecht) and what I calculated, but it's simply formula, so I'm confused. I used:
$$F = \frac{\pi R^2 S}{c}$$
to calculate cumulative force of ...
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Why does the earth and oceans emit primarily infrared photons?
Climate on earth depends a lot on infrared photons being emitted by the earth and its oceans.
I want to know why the atoms in earth elements emit infrared photons after absorbing visible light, UV ...
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How high can you jump (at the corner) on Cube-Earth?
I have read this question:
Is the force of gravity always directed towards the center of mass?
And G. Smith's answer lists a site where they specifically talk about this case mathematically.
https:/...
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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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Schumann resonance frequency
I keep hearing that Schumann resonances have been increasing rapidly in recent years. And that it was relatively stable before. I failed to find any scientific data proving or disproving this. I would ...
