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 the earth keeps the electric potential?
I have the following DC circuit. A cell and a resistor (lightbulb) is serially connected and both ends are grounded. I see the lightbulb is on and hence the current flows.
It is because the electric ...
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2answers
58 views
Is the Moon's rotation affected by Earth's?
There is a lot written on the moon affecting the Earth's rotation but not so much the other way around.
I know that moon has its own rotation:
Tidal locking is the phenomenon by which a body has ...
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4answers
71 views
Is the Earth a gyro?
Due to rotation and low friction, can the Earth be considered a gyroscope? If so, any interesting implications to this? Thanks
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14 views
How do thunderstorms generate ionospheric potential?
In all the explanations of how global electric circuit on Earth works, I've always encountered statements like "thunderstorms generate ionospheric potential" (which is about 250 kV).
E.g. here: https:...
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1answer
35 views
If we could dig up earth's core (inner, outer), would it expand/ density decrease under room pressure/ vaccuum?
This is for science fiction writing purposes. The earth's core is super dense compared to surface materials, partially due to the crazy pressure there. I wonder if we could engineer the whole earth, ...
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28 views
Can a mirage cause the hull of a ship to disappear before the sails?
"Mirage-effect" helps researchers hide objects
The article linked above describes how the effect can be used to make an object disappear.
I am looking into flat earther beliefs and stumbled upon ...
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1answer
37 views
Do we need to know Earth's magnetic field locally?
I'm a high school student and in our course we have elements of earth's magnetic field (dip and other stuff) that lets us know the value and direction of magnetic field at any point on the planet.
I ...
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1answer
73 views
Gravitational field of sun [closed]
Let there be a solar system without Earth.
Now what happen if we place the Earth suddenly on its actual position does the gravitational force of sun acts on it immediately because of its pre ...
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1answer
135 views
Will an object dropped from a high building displace due to the Earth's rotation?
I read that in the 16th and 17th century, the question of whether the Earth rotates around its axis or all celestial bodies rotate around it was extensively debated. One of the anti-rotation arguments ...
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1answer
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Why Earth’s crust is max 100 kms wheras Moon and Mars have much thicker ones?
We know that the Earth’ mantle and core are hot, whereas the crust has cooled down. The cooling process of the 4,5 billion years of the Earth’ exisence resulted a crust of between 50 and 100 kms. ...
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1answer
80 views
Placement of the spaceports on our Earth
Why are spaceports located at certain points (site/place) on our Earth?
Is there a physical reason I don't really know about?
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1answer
66 views
Why is the Earth not an inertial frame of reference?
From many sources I have found the explanation that the Earth is not an inertial frame of reference because it rotates around its axis.
However, nobody mentions the rotation about the Sun.
What I ...
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3answers
72 views
How far can light (packets of photons) travel on earth or atmosphere?
How far can light travel on earth or in the atmosphere?
Or, if I want to be more specific, how far can one photon travel until it disintegrates?
I assume gravitational pull and other effects cause ...
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2answers
141 views
Would a micro black hole keep oscillating around the center of Earth forever?
If a micro black hole was dropped from the surface of the Earth, and that it was too small to absorb particles and eat the Earth, it would fall until emerging from the other side, then fall again and ...
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1answer
341 views
Would a micro black hole have enough energy to heat and liquefy the Earth from within without consuming it first?
Let's say an alien race drops a microscopic 72135 metric ton black hole into the center of the earth. It's Schwarzchild radius is too small (only 0.0001071103 femtometers) so it won't actually be able ...
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2answers
81 views
Which is the most imminent doomsday? [closed]
By "doomsday" I define something which is caused by nature, given that the technological advancement of humanity stays the same as today, and also disregarding possible resource shortages.
For ...
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1answer
84 views
How is the constant “284” derived within the Solar Declination Angle equation?
How is the constant "284" derived within the Solar Declination Angle equation?
The earth's axis results in a day-by-day variation of the angle
between the earth-sun line and the earth's ...
2
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0answers
17 views
Being the Earth modelized as a big magnet (or solenoid), which would be the field intensity of such a model inside the solenoid or magnet axis?
This question has arisen from the Carl Friedrich Gauss’ statement that the Earth could be modeled, concerning his calculations about the earth’s magnetic potential, as a big magnet, himself having ...
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1answer
69 views
Thermodynamics of the Earth’s core
Wikipedia presents conflicting data in the article “Tidal Acceleration”. Hopefully one of you experts can clarify this.
The torque on the Earth is measured at $3.9 \cdot 10^{16}$ yet the tidal ...
2
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1answer
53 views
Why ball fall at same location from where we throw it? [duplicate]
I have a silly question. As we all know earth is rotates at a speed of 460 m per sec. So if I throw a ball in the air for 10 sec than the ball must fall 4600 m away from me but these does not happen ...
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2answers
108 views
In the tunnel through the Earth thought experiment, how does total energy of a particle vary when it goes from surface of the Earth to its center?
In the typical tunnel through the center of the Earth thought experiment, a particle at the surface would oscillate between the two diametrically opposite points ignoring the rotation of the Earth. ...
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0answers
19 views
Why do P-waves cross each other for small angles?
The following is an image produced by ObsPy of P-waves entering the earth just below the surface at small angles depicting the problem:
I wish to understand why the P-wave rays cross each other at ...
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0answers
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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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1answer
57 views
What is the energy source for Earth movements? [closed]
What is the source of energy responsible for Earth movements (rotation, translation, etc.)?
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2answers
78 views
Increase in temperature after an unexpected rain during summer
Why we feel an increase in temperature of atmosphere than usual after an unexpected rain during summer? Usually the raining should have to reduce the temperature of atmosphere.
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0answers
26 views
Neutrino oscillation in earths matter: electron-, proton- and neutron density
I want to incorporate an estimate of a matter effect in atmospheric neutrino oscillations into a model including active and sterile neutrinos. Since neutrinos are not only created in the atmosphere ...
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2answers
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Why is the orbit of the Earth around the Sun very intricate?
The movement of the earth around the sun is very Goldilocky. Did it happen over the years as the orbit of earth averaged out into how it is now? Is there any chance of it (orbit) changing by itself in ...
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2answers
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Does a helicopter that simply hovers remain in the same spot on earth? [duplicate]
Ignoring statistical variation in wind, will a helicopter that only applies force perpendicular to a perfectly sphere earth remain in the exact same spot relative to the earth?
I am arguing with ...
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0answers
48 views
How long would it take for Earth to become desolate after being slung from orbit?
I rather enjoy watching some of the what if scenarios on YouTube, and today I had one trigger my urge to seek out some knowledge on a curiosity I have.
A lot of media out there explains that the ...
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0answers
79 views
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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1answer
80 views
What would happen to the water bodies if gravity ceased to exist on Earth?
If water stopped flowing (it would stop flowing downwards from mountains and all)
then, would it start rising upwards? If it floats on the space ( I say space because there'd not be any atmosphere) ...
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1answer
47 views
Earth rotation with atmosphere
Note: This might be a very dumb question
Considering Earth's rotation on its axis, I was thinking it made sense for the outer sides of the Earth to have a significantly higher tangential speed, ...
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0answers
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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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2answers
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Axis of rotation of the earth
It is known that the axis of rotation of earth is tilted with respect to the perpendicular to the plane of orbit. Is there a way to measure this tilt from earth without the aid of pictures taken from ...
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2answers
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Question about Earth being round, and whether a hypothetical scenario could be true [closed]
I am in no way, shape or form a physicist. This is a question I was debating in my head, and has nothing to do with flat Earth or protesting the Earth is not indeed round. I have a simple question ...
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2answers
76 views
Question About Gravity vs. Earth’s Rotation [duplicate]
If a bullet was fired perfectly straight up (assuming a windless environment) such that the peak of its trajectory was just shy of orbit, would it fall back to Earth in the same spot, or would Earth’s ...
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3answers
232 views
Why is Earth's gravitational acceleration $9.8 \frac{m}{s^2}$? [closed]
How was the value of $g$ determined as 9.8 $\frac{m}{s^2}$?
I am not requesting the derivation but the factors/parameters that influence this value.
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Vertically move in a helicopter to go somewhere on Earth [duplicate]
Is it possible to go from point A to point B (which are on same latitude) by hovering above A and wait till the earth rotates to point B below and then come down vertically?
I believe there would be ...
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3answers
79 views
Inertial frames?
This is from a book.
A traing is moving on earth. A ball is sitting at rest (relative to the train) on the floor of the train which is moving at constant velocity relative to a tree. If the ...
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7answers
192 views
If the Earth is moving, then how is it possible to slow down light? [closed]
Given the following:
Earth is spinning on its axis and also rotating around the sun.
Light has no mass and is not affected by our moving atmosphere
When we slow down light as is done here to a mere ...
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1answer
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How did moment of inertia affect the length of the day? Please try to explain briefly [closed]
How did moment of inertia affect the length of the day? Please try to explain briefly.
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4answers
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How can a day be exactly 24 hours long? [closed]
The longest solar day of year is approximately 24 hours 0 min 30 seconds (occurs at mid to late December) while the shortest solar day of year is approximately 23 hour 59min 38 seconds. If I average ...
0
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1answer
18 views
Electrical systems with multiple connections to earth - is earth modelled as one region of equal potential here?
In the picture we can see a realization of a TT-System, an electrical system with multiple connections to earth at different localiations. I allready know (from this question) that the coulomb-...
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1answer
125 views
Conservation of Angular Momentum — Earth-Moon System — Earth spin backwards?
I am developing an exhibit for a museum. We want to show how the Earth's spin rate changes as the Moon drifts farther and farther out from the Earth. The visitor has a slider they can move to set ...
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1answer
94 views
Why $g$ on equator is less than $g$ on poles? [duplicate]
I found this on my physics book. The book says $g$ on equator 9.78 $m/s^2$ and on the poles 9.81 $m/s^2$. Is it due to gravity?
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2answers
87 views
How much change in Earth's orbital distance to change average temperature by 1°C?
How much closer/farther would the Earth need to be to/from the Sun to effect a $1 \sideset{^{\circ}}{}{\mathrm{C}}$ increase/decrease in average temperature?
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3answers
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Is there a difference between the red sky in the morning and in the evening?
It certainly has a different feeling to it, but
does the temperature or earth's rotation or the clouds
or anything else really make it two different physical
phenomena or at least different colors?
...
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2answers
42 views
Motion at absolute 0 in relative to [duplicate]
Hypothetically, if we could get some type of particle to be at absolute 0 would it be technically still have relative motion due to an observer outside of earth. E.g earth is moving therefor particle ...
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2answers
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Do variations of the Earth's magnetic field affect gravitational acceleration at Earth's surface, and if yes, by how much?
The Earth's magnetic field varies with time over geological time scales (we have phenomena such as pole inversion). Can this affect the acceleration of gravity at Earth's surface? I would think that ...
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0answers
368 views
Why doesn't the Earth lose its magnetic properties? [duplicate]
I learnt in junior high that magnets, when exposed to heat, usually tend to lose their magnetism. Similarly, the Earth's core is also hot, but it doesn't lead to the loss of magnetism of Earth. Am I ...
