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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Effective Radius of Earth [closed]
Hi I am looking for an equation for the effective radius of the Earth. I have a refractive index given by $n^2(r) = 1+\frac{\alpha^2}{\beta^2}$. How would I work out an equation for the effective ...
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Earth colliding into planet-sized object faster than speed of light [duplicate]
Imagine the following scenario:
Earth is travelling in one direction at just over half the speed of light
Another planet-sized object is traveling in the opposite direction towards Earth, also at ...
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Why considering Earth as a continuum gives wrong results? [closed]
Let's consider Earth as a point mass.So,
$$GM=3.9860\times10^{14}\mathrm{m^3s^{-2}}$$
$$R=6.3710\times10^{6}\mathrm{m}.$$
According to Newton,
$$g_{point}=\frac{GM}{R^2}.$$ So,
$$g_{point}=9.8202\...
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Does the Milky Way have any impact on Earth?
Does which galaxy we are in (Milky Way) have any impact on Sun/Earth?
What I mean is: suppose our solar system was instantly teleported into a different galaxy (eg Andromeda). Apart from the stars ...
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Using the sky and ground as a battery
Since there is a voltage difference between the ground and sky, shouldn't I theoretically be able to light a bulb by connecting one terminal to the ground and raising the other one to the sky (via a ...
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Would a gyroscope have solved the longitude problem?
So I was thinking about the longitude problem, which was the problem of determining the longitude at sea. It caused great problems in sea navigation. See: https://en.wikipedia.org/wiki/Longitude#...
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What would happen if the Earth rotated at the rate required to achieve orbit at its radius? I.e ~7k m/s instead of ~460 m/s
To achieve a circular orbit, you need to have a velocity of $$v = \sqrt{Gm/r}$$ which is about 7 km/s at the Earth’s radius, but the Earth’s rotational speed is only about 460 m/s (by taking the ...
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Is the constancy of earth rotation speed the only reason why don't feel the rotation of earth? [duplicate]
i searched the reason of why we don't feel the rotation of earth about its axis but i found the reason is the constancy of its rotation speed ( the rate of rotation velocity is zero )but i find a ...
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Temperature and latitude
Currently I read this excerpt on a school power point that stated the following:
" The sun is closer to the equator than the poles.
Therefore the sun’s rays have less distance to travel to the ...
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Calculate the radio of the earth with a stick like Eratosthenes [duplicate]
I read about how to calculate the radius of the earth like Eratosthenes, but they often said that I should measure the shadow of a stick (usually is a stick) at the time when the solar noon occurs in ...
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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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What's responsible for the earth to rotate and for the objects on it to rotate with it? [duplicate]
Three questions arose to me:
The first is what is responsible for the earth spinning? Is this just newton's first law in action - having been formed out of the material in the cluster of clouds after ...
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Does Earth's electromagnetic field rotate with Earth?
I find sources saying that Earth's magnetic field rotates with Earth, but there are few sources saying that the electromagnetic field rotates with Earth. I realize the question may have a complicated ...
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How did Al-Biruni know the height of a hill?
I knew of Eratosthenes famous experiment for determining the size of the Earth, but a recent question led me to read about another method by Al-Biruni. Like Eratosthenes' method, it required two ...
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How did they know the radius of the earth in ancient times?
We've all heard how in ancient times they determined that the earth was round, and were able to calculate its radius based on the measured shadows of two separate sticks in the ground at noon. I am ...
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How much should I dig a hole to set a post?
I need your help to solve this problem
We suppose that we have a post pulled by
$N=4$ barbed wires separated a distance $dh = 30 \text cm$, and that each wire pulls with a force of
$F=300\text N$ . ...
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Ideas for levitation using Earth's magnetic field and mu-metal [closed]
I'm not sure the idea works or not. Please answer it and its reason.
As shown in Figure 1, when the ASTM A753 Alloy2 magnetic shielding alloy is exposed to an external magnetic field, the applied ...
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Do we have a "good" model for the temperature of the Earth's crust/mantle/core measured from the center of the earth?
Is there a "good" function $f$ that models the temperature of the Earth's crust/mantle/core measured $r$ miles from the center of the earth? By good, I mean a function that strikes a nice ...
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Distance between two points on Earth (arc length) doesn't increase with altitude (radius) according to GPS
Consider the following example:
Point A has coordinates 45 lat, 0 long. Point B has coordinates 45 lat, 2 long. Both points are 5000 ft above sea level. The distance between them is X.
Point C has ...
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What is the connection between Oort clouds and dark matter and dark energy?
I have a research assignment that I can't seem to find much info about, because it's not a very discussed or well theorized topic which is what is the connection between Oort clouds and dark matter ...
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Building orientation - how come both summer and winter solstice used for a facade?
I am planning to build a shed atop my terrace. I was analyzing the sun path to determine the overhang length, facade height etc, but got stuck with a conflict as below.
The summer sun's location peaks ...
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Do neutrons fall to the center of the earth?
Neutrons have no electric charge so they don't interact with the electric and magnetic fields, have mass so they do interact with gravity and are smaller than nuclei so they pass through most atoms, ...
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Does the lithosphere have a resonant frequency?
In meteorological sciences, there is an important concept known as the Schumann resonance, which are the integer values of electromagnetic resonance between the surface and ionosphere. The values ...
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Why does $g$ vary from a direct square relationship inside the earth to an inverse square relationship above the earth's surface?
Why does acceleration due to gravity $g$ vary with altitude, height, and depth from a direct square relationship inside the earth (below the earth's surface) to an inverse square relationship above ...
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If the liquid internal parts of the Earth solidify, what will be the consequences?
Will the Earth's radius just decrease, the daytime decrease, and the magnetic field seize to exist?
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Why is ozone $\rm O_3$ in the Earth's upper atmosphere?
If you look at the density table, you will see that ozone has the highest density among other gases, so why is it in the upper layer of the atmosphere, in the picture I schematically drew how the ...
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If light from a moving emitter has doppler effect would a laser used on Earth show that?
If light from a moving emitter has doppler effect would a laser used on Earth show that? Will the laser have 2 different frequencies when pointed in 2 opposite directions on Earth due to Earth's ...
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How many full orbits around the galactic center our Earth has done so far since its creation?
I have read that the estimated age of our Milky Way galaxy is 13.61 billion years which is by using our current size and status of our galaxy about 59.17 Galactic years which each galactic year ...
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How close can Jupiter be to Earth without making Earth unhabitable? [closed]
How close can Jupiter be to Earth without making Earth unhabitable? What's the closest distance possible? Can Jupiter be twice or three or four times as close to Earth as Mars without having any ...
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Approximating the warmest time of day
I'm trying to find a very simple approximation of when the maximum air temperature will occur on a given day at a given location. By "air temperature," I just mean the air temperature at ...
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Why is Earth considered an inertial frame of reference in common examples of interstellar relativistic motion?
Such as in the twins paradox. If relativity requires inertial frames to be applicable then how does a rotating, revolving planet count?
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Lag in Direction of Earth-Sun Gravity vector
When the earth is orbiting around the sun, it experiences a force vector pulling it towards the sun, which acts as a centripetal force for its elliptical orbit. However, when the earth moves a bit ...
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How can we feel Earth magnetic field if we are rotating with it?
I know Earth have molten iron core and we should feel a magnetic force if we are stationary while Earth is spinning. But I'm curious how it is we can feel north and south poles so distinctly while we ...
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Will angular velocity of earth be Affected By this? [duplicate]
If all the humans, animals, and all other beings came together to North Pole of earth, Will it affect the angular velocity Of earth in any means?
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Structure of space time inside Earth
What's the structure of space time inside the Earth? If time in the middle of Earth is different from the outer can this explain geological processes and is our knowledge of its internal structure ...
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Is any fusion or fission happening at the center of Earth? [duplicate]
High pressure, temperature same as the surface of the Sun, solid iron inner core, liquid outer heavy elements core - got it. But are nuclear reactions happening there?
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What would happen if a teaspoon of neutronium crashed through Earth's atmosphere? [duplicate]
Pretty self explanatory hypothetical. I realize this is probably an impossibility and maybe it'd be more likely to be hit by a small black hole or primordial black hole. I'm just curious, because we ...
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Would a projectile launched with the escape velocity reach a final velocity of 0 as time approached infinity?
I just wanted to check my understanding of escape velocity.
If a projectile was to launch and have the exact velocity as the escape velocity of the earth,
it would have a final velocity of 0 correct?
...
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Which location on Earth has the strongest deviation from the vertical due to gravity?
So, I've recently learned about the Schiehallion experiment, performed in 1774, where scientists detected the deviation from the vertical of a plumb due to the gravitational attraction of a single ...
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Can anyone explain how does an object move upward from the surface of the earth defying the spacetime curvature?
I am trying to understand the while concept of spacetime curvature. Space is a fabric which is bent by heavy masses. But I don't understand that why objects follow the geodesics and get attracted to ...
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What volume would the mass of Earth occupy in the core of the sun?
I was just wondering if anyone had computed this. I read that the pressure in the Sun's core is 3.84 trillion psi. Obviously the mass of an Earth-sized object in the core would be millions of times ...
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The effect of gravitational lensing during the lunar eclipse
During the lunar eclipse, the Moon turns into bloody colour while the shadow of the Earth is casting over the lunar surface. The red hue can be explained by means of the refraction of light and ...
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What is the motion of the Earth compared with cosmic background radiation? [duplicate]
Does cosmic background radiation have a frame of reference where it is symmetrical in all directions? If so, what is the motion of this planet, solar system, or galaxy with respect to this?
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How long would it take for down becoming the opposite on earth?
Sorry if the question is unclear, I will try to explain it better.
Let's say that I am standing still somewhere on the planet and I say while pointing at my feet :"Down is this way", how ...
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Was Eratosthenes justified in his belief the earth was round? [closed]
Because I see two flaws with it, firstly he assumes the distance of the sun won't affect the angle at which light hits the pole. If the sun were far closer and far smaller, there would be a change in ...
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When the Earth suddenly stops pulling [closed]
Let's say the Earth stops attracting objects to itself all of a sudden. So, I was wondering what would happen to a person standing on the surface of the Earth? (Neglect the effect of the rotation of ...
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Earth electromagnetic field
Nowadays an unlimited amount of information can be transferred around the planet using wireless methods.
Is that possible to transfer the information using natural electromagnetic field such as Earth ...
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Charging one plate of capacitor and grounding the other plate of capacitor
I want to learn about this way of charging the capacitor. At my university, we charge capacitor with power supply. Its negative power supply. Power supply is grounded (earthed). A conductor from power ...
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How is lava ferrous oxides responding to Earth's magnetic field related to Curie temperature?
One of the evidences of Earth's magnetic field oscilations are different magnetic orientations of lava particles that pop up on the surface at several volcanic locations at several chronologic stages ...
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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?
