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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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 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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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 ...
user324347
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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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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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Rate of neutrino generation in Earth's core?
I know that there are radioactive elements present in the Earth's core, but has anyone determined how much? That is, do we have an estimate of the number of neutrinos per second generated within the ...
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Atmospheres and oceans on lower gravity planets
Using Earth as an example, how much less gravity could the planet exert and still retain its atmosphere and oceans? Or is it a matter of size, mass, magnetosphere, place in the solar system, all of ...
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What path would it produce if someone kept on going after their shadow (on Earth)?
Imagine someone is standing on the surface of the Earth (let's assume it is completely flat) and they start going exactly in the direction their shadow is cast (that is, exactly opposite of where the ...
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Would the Earth have weighed the same if no life had developed on it?
I was reading this question and talking about it with my flatmate when a question came up. Ignoring the effects of losing or gaining mass due to cosmic dust, meteorites, and atmospheric losses as ...
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Difference between Critical and orbital velocity
What is the difference between orbital and critical velocity of satallite ?
I have read that critical velocity is constant value and it does not depend upon altitude. It only gives the velocity of ...
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Earth's surface area
Here we are trying to calculate the earth's surface area via geodetic coordinates:
\begin{align}
x&=(R\,p(\lambda)+h)\sin\lambda\,\cos\phi\\
y&=(R\,p(\lambda)+h)\sin\lambda\,\sin\phi\\
z&...
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Is the period a physical observable in General Relativity?
I am currently seeing the classical tests of GR. To justify the introduction of a test based on the Doppler effect, the professor says that the previous test ( Shapiro and echo-radar test ) is based ...
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How much time does it take in Earth to generate the energy supply that the sun produces in one second?
According to this article which I ignore if it's correct The amount of energy the sun emits every second is , the amount of energy the sun emits by second is $4\times10^{33}$ ergs . And according to ...
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How can I obtain the position of the Earth on the orbit for given date?
I would like to be able calculate (or at least download some time-series data of) the position of the Earth on it's orbit at given date. For my purposes, it would be sufficient to account for the ...
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Does Earth's precession rate change with the seasons?
As Earth's precession is caused by the differential solar, etc., attraction to its 'spare tire', then does the rate go to ~zero at the equinoxes and ~twice the average at the solstices? (preferred ...
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