The study of the physical processes and properties of the planet Earth. Applicable to many subjects about Earth, such as its shape, its magnetic field, and ocean currents.

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Extinction level meteor effects on Earth's crust pending on the surface area upon impact

Would it be possible to have a extinction level meteor hit Earth depending on shape to actually create minimal damage if turned on its thinnest area rather than hitting flat? The meteor would enter ...
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0answers
7 views

Infer geophysical underground structure from thermal photography of the ground

Is it possible to determine (approximately of course) the geophysical structure of the underground under a certain region, using only a thermographic picture of the upper ground of the region ? The ...
0
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1answer
42 views

Does the shape of a meteor make any difference during an impact? [on hold]

Would the shape of the meteor make a difference on the impact? Like a Olympic diver would a spear shaped meteor make less damage to the surface of the Earth while creating more magma movement rather ...
2
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4answers
400 views

Why does solid turn to liquid deep in the Earth? [duplicate]

Usually pressure decreases inter-molecular movement thereby keeping the substance in solid state. Given this, why do the earth's crust and mantle, which are both solid, turn into a liquid outer core, ...
0
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1answer
60 views

How noticeable is the gravitational pull of a mountain range?

A massive object like a planet exerts a great gravitational pull on nearby objects. This will cause them to accelerate towards the center of the planet with the same acceleration regardless of their ...
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0answers
42 views

What started the magnetic field of Earth [duplicate]

The Dynamo theory gives a good explanation of the magnetic field of the Earth: the Coriolis force focus inner currents into current spirals generating magnetic(s) field(s). What I'm trying to ...
22
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4answers
2k views

Difference between sunrise and sunset?

Other than knowing which direction is east and which direction is west, or observing for a sufficient timespan (to determine the direction of motion), is there any way of telling whether what one is ...
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0answers
11 views

Standard Minimal Reference Set of Poroelastic Parameters

I am coding a poroelastic reservoir simulator which requires the input of poroelastic parameters of the reservoir rocks. Detournay and Cheng, "Fundamentals of Poroelasticity" (1993) state that: ...
46
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4answers
3k views

Why do some location on Earth have only one tidal maximum per day instead of two?

Most places in the ocean have two high tides and two low tides per "day" (~25 hours). But I remember reading that some locations only have one of each per day. This answer has some great explanations ...
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3answers
172 views

Why geologist do not consider molten iron in the magma to be the source of Earth's magnetic field?

This was a question that came in a exam. How come is this possible? Actually, a question on the source of Earth's magnetic field was asked here on physics SE, which matches my opinion. The ...
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2answers
36 views

How to combine albedos

I have estimations of the Earth's surface albedo for a region (0.13), as well as an estimation of the atmosphere albedo (0.3 at a solar zenith angle of 1 rad). My question is, how do I find the ...
4
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1answer
56 views

How much of Ultraviolet is cut out when Sun moves to the Horizon?

EDIT: Original question was whether or not we need to wear sunglasses when Sun is at the horizon. But it was confusing to many users whether it is on-topic or not. So the details are adjusted. From ...
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1answer
35 views

Could we pump up (or deplete) the Earth's magnetic field?

This text calculates the energy in the Earth's field as about 10^17 Joules, and adds: A typical power station is a giga watt, and the number of seconds in a year is about 3 × 10^7 so a power ...
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1answer
69 views

(Constant) Value Of Gravitational Pull $g$ Of Earth [closed]

I want to know How the value of $g$ was found and what experiments did Newton conduct to land upon the value that we use, which is 9.8 m/s^2. I tried to search for it but I couldn't find much ...
3
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1answer
66 views

Is it possible to 'push' a path to the Earth's core?

This may very well be a question for Earth Science SE, but as it is very hypothetical, maybe pure physics is more appropriate... Question: Imagine we have have a wedge that tapers down into an ...
5
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1answer
94 views

What's the distance between the center of mass and geometrical center of Earth? [closed]

With a good approach we can say that they are identical. But how accurate is this approach? Since Earth is not homogeneous there must be (can be) some difference. In other words I'm asking if Earth ...
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2answers
76 views

The Strength of the Tangential and Radial Components of a Dipole Magnetic Field

I am following along well several textbooks (Geophysics) that helps me understand the in-depth physics behind the magnetic field of a dipole magnet. I understand that the basic magnetic potential (...
0
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2answers
44 views

Height of oceans after ices of poles are melted

As you know if we put a cube of ice on a glass of water because of floating force it will be floated. if we measure the height of water in that time it has no difference with the time that ice is ...
65
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5answers
12k views

Why is it cold on the sea floor if pressure heats things?

I was reading this and it says that Microsoft put a server farm at the bottom of the ocean because it's cooler there. Particularly it seems to imply that it get's colder as you go deeper, "Since ocean ...
22
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11answers
3k views

Backyard experiments to falsify the Flat Earth theory [duplicate]

I recently became aware that the flat Earth theory still exists in the 21st century, and has colored the views of a friend of mine. Roughly speaking, the tenets are: The Earth is a flat disk, with ...
0
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0answers
23 views

Rate of Convection

Today in Geophysics the professor briefly introduced the mantle convection processes how it rises and drops. He also said this generates Earths magnetic field and we know that Earth Magnetic field ...
1
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1answer
72 views

Infinite elastic half-space with point load (Mindlin's problem)

What is the equilibrium deformation of an infinite half-space (that is, an isotropic and homogeneous linearly-elastic three-dimensional medium, with a single planar surface) produced by a force which ...
2
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1answer
108 views

Are low pressure and high pressure areas responsible for rain?

My understanding is that low pressure areas are susceptible to rain. However, high pressure areas have no rain. Now, I want to correlate this with the following areas - Lower Hutt, Wellington , NZ - ...
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2answers
43 views

Why is the sound channel in the ocean especially good for low frequency sound?

Why does not the high frequency sound propagate as far? The dispersion curve $\omega(k)$ is almost linear, right?
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0answers
29 views

A question about the sound channel in the ocean

The sound channel (SOFAR channel) in the ocean is about 1000 meters below the surface. It is said that sound can get trapped in this channel and propagates thousand kilometers without dissipation, ...
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0answers
43 views

Charge on Earth [closed]

We know that the Earth is neutral. But what will happen if the Earth becomes negatively charged or positively charged somehow?
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0answers
52 views

As the World Turns [closed]

Does the Earth's axis change with the magnetic reversal as it is taking place?
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1answer
209 views

Earth Maybe a Compass or Not [closed]

Does the Earth magnetic pole point to something in our solar system or farther? Like the Sun.
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0answers
60 views

Is there a theoretical maximum speed for wind?

What we call wind is actually molecules moving into an area of lower particle density due to their thermal motion. A lower particle density offers less collisions (resistance), so more molecules move ...
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2answers
133 views

Why is the acceleration due to gravity $g$ quoted as if it were constant?

In elementary physics courses the value $g=9.8\:\mathrm{m/s^2}$ is used almost universally. But surely this value must depend to some extent upon one's location on the Earth. Why do we assume a ...
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0answers
68 views

Why are the cores of planets melted?

We all know that the core of Earth is in liquid form, as are most other planets as recently read. Why is this the case? Obviously, high temperatures are the cause, but what causes the high ...
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0answers
41 views

How does magnetic field gets generated by friction between high temperature molten metallic cores?

I was watching "Strip the cosmos" show on Discovery science channel last day and they explained that earth produces magnetic field due to rubbing of the two concentric cores, both the molten metal ...
-1
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1answer
28 views

Variations of earth's magnetic field strength [closed]

Is it true that on average, people who grow up in a geographical location of the earth where the magnetic field strength is stronger than other geographical locations, develop more to their genetic ...
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0answers
10 views

Variations of earth's magnetic field strength among different geographical locations [duplicate]

Is it true that on average, people who grow up in a geographical location of the earth where the magnetic field strength is stronger than other geographical locations, develop more to their genetic ...
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2answers
71 views

How do gravity anomalies on Earth comply with conservation of energy?

Gravitational acceleration varies from place to place on Earth in a range of about 0.02 percent and is caused by density distributions within the Earth. Imagine an experiment where you move around the ...
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1answer
251 views

How loud would a sound have to be to be heard around the world?

I'm reading the book Cosmos by Carl Sagan, and in it he states: Striking the Earth's atmosphere, a modest cometary fragment would produce a great radiant fireball and a mighty blast wave, which ...
3
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2answers
347 views

How strong would the Earth's “magnet” be if it was the size of a fridge magnet?

If you shrunk the "magnetic part" from inside the Earth down to a fridge magnet size, how strong would it be in Gauss? This is not a home work question. I just watched this video which included the ...
4
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2answers
630 views

Rivers that flow “uphill” due to Earth's rotation

One of the fun tidbits that gets bandied around in physics departments is that the Mississippi River actually flows away from the center of the Earth. Due to the Earth's oblateness, the source of the ...
2
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1answer
97 views

Why is it that not the entire surface of Earth is covered by water? [closed]

Isn't it a coincidence that our planet is mostly but not completely covered by water? Is there a reason why less water or more water is not compatible with intelligent life? Also, isn't it a ...
1
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1answer
75 views

Earth density distribution from shooting neutrinos?

I am interested in possibility of inferring Earth interior structure from gravitational data. As classical calculus problem shows, it is impossible to understand non-uniform density distribution ...
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3answers
232 views

Is gravity actually missing or lower in certain spots on Earth?

I have heard and read about "missing gravity" in some regions of Earth. What I seemed to gather from this info is that if I go to a certain spot and jump, I can jump higher; or I could maybe lift more ...
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2answers
79 views

Estimation of the age of Earth

By calculating the ratio of U-238 to Pb - 209 the age of the earth can be estimated. Is it not a possibility that non radioactive lead already there formed during the birth of earth it self alter the ...
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0answers
26 views

Could the assumption of superconductivity explain unexplained geomagnetic behaviors?

Science recently published an article regarding a new discovery in superconductivity; that the metallic form of hydrogen sulfide is superconducting at high temperature (relative to absolute zero). I'...
0
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1answer
109 views

What is causing the Trumpet Sounds that are emited from the sky?

In these last years, a phenomenon have appeared in several countries (US, Canada, Australia, Russia, Germany, and others). It consists of sounds like a trumpet coming from our own planet's sky. [It'...
5
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2answers
263 views

Why doesn't the sun reflect off Earth's oceans from space like a billiard ball?

According to Phil Plait, Earth is proportionally smoother than a billiard ball (http://blogs.discovermagazine.com/badastronomy/2008/09/08/ten-things-you-dont-know-about-the-earth). The water surface ...
0
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0answers
49 views

What will be the affect of Global Warming if Polar Ice melts? [duplicate]

Due to global warming, all the polar ice melts & sea level increases, with increase in humidity. Angular momentum of ice at pole is, very low. Due to shift of water, from pole to equator, it's ...
0
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2answers
128 views

If 1% of total water in earth evaporates to the atmosphere due to Global Warming, what will happen? [closed]

My views Atmospheric volume increases. Mesosphere's temperature will increase. Resulting no rainfall. Some H2O molecules will escape to the space. Rotation of Earth will slow down, resulting the ...
2
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0answers
29 views

How much UV light do we have on the ground? [closed]

We cannot see it. But suppose each UV photon is replaced by a red light photon, does it make the world look as bright as it is just before the sunrise?
37
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3answers
7k views

In atomic bomb tests under ground, where does the volume of the rocks go?

Underground atomic bomb tests are done in a deep, sealed hole. Not all underground tests eject material on the surface. In this case, they are only noticeable as earthquakes, according to german ...
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0answers
93 views

Can one verify the Earth tide in his yard?

The ocean tide you can see on the coast. But the Earth tide beneath our feet is hardly perceivable. Is there any way to verify it in one's yard?