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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Where does the energy of a lightning strike go?

Lightning contains a lot of energy, so where does this energy go after lightning has hit the ground? Does it travel all the way to the core? What happens after that?
62
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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 ...
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11answers
2k 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 ...
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0answers
22 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 ...
8
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1answer
146 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 ...
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0answers
15 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 ...
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1answer
50 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
28 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
21 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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2answers
4k views

What if the earth's core goes cold?

What effects would occur if the earth's core goes cold? Would the planet stay liveable after this happens?
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2answers
8k views

What is the net charge of the Earth?

This question arose in a seminar today about the solar wind... This is my vagueish understanding of the problem - please correct if you see errors! The 'classical' picture of atmospheric electricity ...
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0answers
33 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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1answer
165 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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1answer
742 views

Why is the geomagnetic north pole at a different location from the magnetic north pole?

According to this site Magnetic North, Geomagnetic and Magnetic Poles The Geomagnetic poles (dipole poles) are the intersections of the Earth's surface and the axis of a bar magnet hypothetically ...
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0answers
49 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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7answers
7k views

If the gravity at the center of the Earth is zero, why are heavy elements like iron there?

If gravity is zero at the center of the earth, why is there a core of heavy elements, such as iron? Alternate question for the opposite hypothesis: If gravity is greatest at the center of the ...
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votes
2answers
621 views

what determines the wavelength of waves on the open ocean?

Looking at the picture below, you can totally see that these are tiny boats. The water is practically washing over the hull of these boat models. But the water has boundaries that are very far ...
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2answers
112 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 ...
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2answers
2k views

Why does Earth behave like Natural Bar Magnet?

What is the reason for the Earth to behave like a bar magnet and have poles (North and South poles)?
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1answer
96 views

What is the longitudinal difference between the sub­solar point and the magnetic poles at time $t$ (hours)?

I'm trying to convert geomagnetic coordinate to geographic, but there are some steps in the paper which I'm reading, that I don't understand. I have the geomagnetic latitude centered around the ...
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0answers
45 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
96 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
60 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
28 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 ...
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2answers
800 views

Why isn't the Earth's core temperature the average of its surface temperatures?

Assuming that the earth is spherical, that its temperature is continuous, and that some other more or less realistic conditions hold, we might think that the Earth's core temperature should be about ...
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1answer
26 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
9 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
61 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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2answers
1k views

Why heavy elements don't sink to the core?

If earth assembled out of space dust, how come we find heavy elements like gold, silver, uranium and bunch of others that are heavier than iron on the surface? I mean silicon (Si mass 28.084) being ...
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0answers
31 views

The Earth's gravitational magnetics [closed]

The Earth has magnetic properties correct, so can they be measured and if so what are some consistencies?☆
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2answers
280 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 ...
41
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5answers
8k views

Why has Earth's core not become solid?

The Earth is billions of years old, yet its core has not yet cooled down and become solid. Will this happen in the foreseeable future?
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1answer
77 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 ...
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2answers
77 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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3answers
134 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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1answer
63 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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0answers
24 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). ...
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1answer
155 views

Why does air contain $Ar$ specifically?

Air consists roughly of $N_2$, $O_2$ and $Ar$. Why is $Ar$ the relatively common noble gas compound and not for example the lighter ones $He$ or $Ne$?
81
votes
7answers
9k views

Why is there a scarcity of lithium?

One of the major impediments to the widespread adoption of electric cars is a shortage of lithium for the batteries. I read an article a while back that says that there is simply not enough lithium ...
0
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1answer
105 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. ...
5
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2answers
179 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 ...
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0answers
47 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
109 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
26 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?
2
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2answers
89 views

Frequency of earthquakes

Are earthquakes getting less frequent across the centuries? I know that more seismic stations have register more earthquakes in the last century, but that doesn't imply there were more. I am ...
37
votes
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 ...
3
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0answers
78 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?
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1answer
46 views

Helium confined to a gravity well

It's a well known problem that Earth is slowly losing its supply of helium due to helium's ability to "bubble off" the atmosphere. All the gas giants have significant percentages of helium in their ...
2
votes
0answers
14 views

How much heat is transported from the interior to the surface in the form of hydration enthalpy?

Heat is transferred from the interior to the surface through several methods. One is simply the conduction of sensible heat through the crust - I would guess this accounts for most of it. But some is ...
0
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0answers
26 views

Does sun's geographical(not magnetic) polarity changes?

What i am asking is, do sun's north pole & south pole reverses, resulting rotation change?