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 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
51 views
What is the energy source for Earth movements? [on hold]
What is the source of energy responsible for Earth movements (rotation, translation, etc.)?
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69 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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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
92 views
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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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
61 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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Geometry of the Earth [migrated]
Is this true that every simple closed curve on the earth can be deformed continuously to a point without leaving the earth?
Is the earth compact?
Now if we consider the earth as a 2-manifold, can we ...
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1answer
74 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
42 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
80 views
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
72 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
155 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
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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
190 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 ...
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1answer
15 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
73 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
57 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
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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
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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 ...
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0answers
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Estimating the Pressure of Earth's Center
The pressure of a medium of density $\rho$ and in a graviational field with strength $g$ at a depth of $z+dz$ is equal to the pressure at $z$ plus the pressure caused by the weight of a slab of volume ...
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0answers
67 views
A confusion between geocentric and heliocentric model [duplicate]
As per Ptolemy, he proposed firstly geocentric model and that model if one see with aspects of relativity he would find true. Here is an example how
Suppose you are in a train which is moving and you ...
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1answer
60 views
How much does temperature affect the time of sunrise?
Please forgive me if this is a dumb question, or if my understanding of basic physics is wrong. Please feel free to correct me.
As I understand it, if the Earth didn't have any atmosphere, then the ...
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1answer
44 views
How fast would an object at cruising altitude (around 10,600 m) need to travel to stay on the opposite side of the Earth to the Moon? [closed]
I am trying to figure out how fast an object will have to travel (at a height around 10,600 m) to never be in the presence of the moon. Meaning the object will always be on the opposite side of the ...
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1answer
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Did Eratosthenes make his measurements on the same day?
Erasthosenes measured the circumference of the earth on the summer solstice by observing the sun at Alexandria and Syene.
Was this done on the same day in one year or on the same day in two ...
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1answer
49 views
If I drive East, how much lighter am I than if I drive West?
I'm at the equator. Suppose I am driving at x kph, in the direction of the Earth's rotation (i.e. due East), I presume that the force my vehicle exerts on the ground is less than when I am stationary. ...
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1answer
43 views
How does the Earth's radial acceleration affect it's velocity during orbit around Sun? [closed]
When the earth moves along its ellipse at $67,000mph $ it accelerates at $0.006m/s^2$ would it be correct to say it's speed at some points relatively increases by $0.006m/s$ every second
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1answer
57 views
What's the Earth's linear acceleration component around the Sun?
The earth's centripetal acceleration around the Sun is $0.006m/s^2$ does this mean one can say the earth's acceleration when it travels(revolves) at $670,000mph$ is simply equal to its centripetal ...
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Large objects in the universe sized by gravitational and electrical constants
In a famous talk (from 14:30 to 15:00) Nima Arkani-Hamed tells us that what "fixes the size of the earth" is the equilibrium between the gravitational pressure against the atomic pressure of the atoms ...
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Does current flow when you connect a battery to earth?
Let's say that the earth has 0V and everything is ideal,
does current still flow and why?
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31 views
Need an equation to calculate the list of latitudes and longitudes of an off-nadir sensor with a given half angle
I need a deterministic way to determine a list of latitude and longitudes of an off-nadir pointing sensor for a given half angle. Below is a depiction of the problem.
It isn't too hard to calculate ...
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1answer
88 views
Is gravitation on earth less in nighttime than in daytime?
I have been thinking on the effect of the centrifugal/centripetal forces from the orbital movement of the earth around the sun, which might perhaps affect the gravity.
In nighttime we are on the ...
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2answers
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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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2answers
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Is one side of earth faster at night and slower at daytime?
I'm reading Physics for Entertainment by Yakov Perelman and in it he says under "When we move around the sun faster" that at midnight the speed of the rotation of the earth is added to that of earth's ...
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1answer
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Measuring the earth's electric field
My question stems from a question on the Dutch VWO-level highschool state exam (from 1993) concerning a device to measure the earth's electric field. It consists of two plates positioned above one ...
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1answer
63 views
Is the Earth orbiting an 'illusory' Sun, owing to the 'speed' of gravity? [duplicate]
We see the Sun about eight minutes after light left it. Presumably this means we are also experiencing the Sun's gravity 8 minutes after it 'left' the Sun.
So are we orbiting around the Sun we can ...
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4answers
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Is Earth an inertial reference frame?
Is earth considered as inertial frame? i was confused because we learned about coriolis effect. We know that earth spins therefore coriolis effect should take place . But does it have minimal effect ...
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2answers
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Can magnets be arranged to interact with earths magnetic field to produce force?
Is it possible to arrange one or more magnets along with iron/ferric guides to interact with our planets magnetic field in such a way that a force is generated in one or more directions?
Would a ...
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1answer
484 views
How do we know the Earth's core is Molten with Seismology?
My current knowledge about how the core of the earth was discovered is the observation made from non returning/reflecting sonar signal when sent to deeper depths through the earth's crust/mantle. How ...
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If the Earth would change into a ball of water, how wil its form develop, considering only the Sun's and Moon's influence? [duplicate]
Let's fantasize that the Earth changes in a non-rotating ball of water. And let's assume the only gravitational influences on it are those of the Sun and Moon.
What will happen to the form of the ...
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2answers
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What happens to the water on the surface of the Earth if the Earth is not rotating about its axis in the Earth-Moon system?
Suppose the Earth is not rotating. As usual, the Moon follows its normal path around the Earth. Let's assume it's a circular motion and that there are no other gravitational influences.
A test ...
