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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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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1answer
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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?
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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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How does formula for universal gravitation between mass $M$ and mass $m$ collapse to $mg$ on Earth? [duplicate]
Can anyone give a mathematical demonstration of this? I assume it has to do with the fact that Earth’s mass is much bigger than the mass of any object on Earth, but I think it would be interesting to ...
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1answer
86 views
Why do moving liquid metals generate a magnetic field?
The earth's magnetic field is generated due to the movement of liquid metals, but why not solid? Why is it that moving molten metals create a magnetic field, but when nothing of the sort happens when ...
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Why and when can the Earth be considered an inertial reference frame?
The question has been asked (e.g., here and here), but I would like to get a more definitive and mathematically formal answer.
The Earth rotates around its axis, around the Sun, and participates in ...
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Simple, vivid way to demonstrate the rotation of the Earth
What is a simple, vivid and compact way to demonstrate the rotation of the Earth? Something you could keep on your desk and that a middle-schooler or flat-earther could understand?
I considered ...
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What is Earth's linear velocity around the Sun?
I am creating a theoretical model of the Earth's tangential acceleration around the Sun (on an elliptical orbit, not circular). First, I will build a theoretical model, which is not influenced by any ...
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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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Best latitude to harness solar power during June?
What is the best latitude at which to place a solar panel during the month of June? Assume for simplicity that any any given latitude there is a place without clouds or large mountains to obstruct the ...
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1answer
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If we point a perpendicular laser beam from the bottom of a skyscraper to its peak should that beam be inclined?
If we point a perpendicular laser beam from the bottom of a skyscraper to its peak should the beam be inclined due to Earth's motion+rotation even the pulse is making a perpendicular trajectory?
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How can the change of the Earth's temperature be determined with more than 1/10 K accuracy as IPCC suggests?
How can one determine the extent of global warming (expressed as a temperature difference) with such precision? The latest IPCC report states temperature changes to fractions of one degree - without ...
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Didactic model for tipping dynamics [closed]
I would like to know if there are some toy models that describe a system dynamic from ecology or earth science with some feedback loops (eg. ice-sheet cover, rainforest-savanna cover, permafrost ...
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Earth's core must be producing light, where is that light energy going?
Earth core is about 5000°C hot. It must be producing light but no one can see it. So where is that light energy going? It isn't escaping to space for sure.
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If an object stays afloat in air for long enough, will it start moving backward eventually? [duplicate]
Let's say, for example, if a helicopter that has an unlimited fuel supply and everything else needed to stay functional stays afloat in air for long enough, would it eventually start moving backwards? ...
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Does gravity get stronger the higher up you are on a mountain?
So I saw this article stating that gravity is stronger on the top on the mountain due to there being more mass under you however I have read some questions other people have asked and most of the ...
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How much of Earth's mass is created by the energy of the core?
I've read that higher energy means higher mass, and in atomic systems, the kinetic energy and potential energy actually contributes more mass than the actual particles themselves (or so I've read). So,...
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2answers
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Why doesn' t the sky look blue from outer space? [duplicate]
The sky looks blue because blue sunlight is scattered all over the atmosphere. Doesn't the same take place in the other direction? From Earth to the sky? So the atmosphere would look blue in outer ...
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2answers
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Why does the horizon visually appear curved at high altitudes?
As I understand it, the horizon is essentially a circle, since it would result from the intersection of a cone (yours or a camera's projected view surface) with the spherical Earth. Please correct me ...
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2answers
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What is the difference of gravity between lowest tides and highest tides?
I know tides are due to gravitional gradients so the difference of gravity between places does not need to be big in order to generate tides.
Regardless, what difference are we talking about, ...
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4answers
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Is it possible to use forces on a current carrying conductor due to Earth's Magnetic field to levitate?
When current is applied, a conductor within a magnetic field feel a force. This is the Lorentz Force. I was thinking if it is then possible to apply as much current on a conductor that it will start ...
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Could metal rods conduct geothermal energy to the surface?
Currently geothermal heat pumps circulate a working fluid through a loop running in either a deep well or a long series of more shallow trenches. Boring a well is expensive and digging trenches chews ...
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Pressure at the base of an air column 6371 km high
If you allow me some imagination, without laughing, then I can assume that I dug a very vertical hole, come on, let's say 1 m2 of section to fix the ideas, which crosses the Earth through its center, ...
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Is Earth’s rotation slowing down or speeding up?
Section ‘Slowing down of the Earth’ of the Wikipedia article Leap second has the following paragraphs:
A mathematical model of the variations in the length of the solar day was developed by F. R. ...
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Alfven waves in the ionosphere
I was given the following problem/question as a part of my homework in physics:
It is raining with thunder in Australia, and the lightnings generate transverse Alfven waves in the ionospheric plasma. ...
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1answer
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How does grounding (burying a terminal underground) complete a circuit?
I am having some trouble with the concept of grounding the electric supply.
The doubt is basically : if I hold a live wire standing on the ground, why do I get a shock?.
Please don't say there exist a ...
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If the Earth is constantly accelerating at 9.8m/s^2, according to General Relativity, won't Earth's speed be constantly increasing towards infinity? [duplicate]
As per Einstein's Theory of General Relativity, I understand that 'the Earth's ground is accelerating towards us at 9.8m/s^2. This is why we're falling towards the center of the Earth, as GR doesn't ...
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Is it possible to estimate the 23.5° tilt of Earth's axis?
Using the value of the precession of Earth's axis in 25,800 years and the value of Earth's radius, mass, moment of inertia etc., would it be possible to calculate/estimate that Earth's axis must be ...
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Why doesn't the Earth's temperature increase in the perihelion?
I know that what causes seasons in earth is the tilt of the earth and the fact that sun rays reach the earth from different angles during winter and summer, but why doesn't the temperature of the ...
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Is it a coincidence that distance between Sun and Earth=(Distance between Earth and Moon)*(365.25+24) or is there any logical reasoning behind it? [closed]
Here $365.25$ days is the time taken for Earth's Revolution around the Sun while $24$ hours is the Earth's rotation.
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What would happen if I shot a near-light-speed bullet at the moon? [closed]
What would happen if I shot a bullet at 90% of light speed from earth to the moon? Would it make it through the atmosphere? Would it have any negative effects on the earth's atmosphere as it passes ...
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Earths electric charge: is it neutral?
Is the whole earth electric neutral? I know about the negative charge of the earths surface and the positive charge of the ionosphere, but i wonder if the whole earth (including its atmosphere) has an ...
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Gravity is not a force - how does "accelerating up" work for the entire earth? [duplicate]
So this question has been bothering me for several days now. I've seen many YouTube videos on how "Gravity is not a Force", but no one seems to offer a simple explanation on how does this &...
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Does anyone know where I can find values of gravity?
Does anyone know where I can find the values of gravity at different places across the globe and at different heights? I am doing an assessment on gravity and can't find any data for the values of ...
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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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After the discovery of the "unicorn" black hole, how likely is the Earth to be hit by a blackhole?
We know that the earth's chances to be hit by a blackhole before the death of the sun were practically 0 but how do the odds change after the discovery of the unicorn?
About the unicorn:
https://www....
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Have Einstein's field equations ever been solved for Earth? [closed]
If not, what remains unknown that prevents a solution?
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What would happen if all water on Earth froze instantaneously? [closed]
What will happen if all water on the surface of the Earth froze instantaneously? Let's take into consideration only the non-frozen part of the oceans, which comes close to all water on the surface.
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Can a pendulum at resting equilibrium position still demonstrate the Earth's rotation?
I conducted an experiment in my youth, creating a 'sand pendulum' hanging from the bedroom ceiling to a bowl of flour. I did not set the pendulum into motion, but rather wanted to see if the force of ...
