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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Simple check for the global shape of the Earth
I have been on a date recently, and everything went fine until the moment the girl has told me that the Earth is flat. After realizing she was not trolling me, and trying to provide her with a couple ...
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How do I explain to a six year old why people on the other side of the Earth don't fall off? [closed]
Today a friend's six year old sister asked me the question "why don't people on the other side of the earth fall off?". I tried to explain that the Earth is a huge sphere and there's a special force ...
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Why doesn't the Moon fall onto the Earth?
Why doesn't the Moon fall onto the Earth? For that matter, why doesn't anything rotating a larger body ever fall onto the larger body?
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What is the simplest way to prove the Earth is round?
Assume you've come in contact with a tribe of people cut off from the rest of the world, or you've gone back in time several thousand years, or (more likely) you've got a numbskull cousin.
How would ...
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Why does CNN's ‘gravity hole’ in the Indian Ocean dip the sea level instead of raising it?
Ref. There is a ‘gravity hole’ in the Indian Ocean, and scientists now think they know why
According to CNN, the 'gravity hole' is an area of decreased gravity, compared with the surroundings. This ...
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How does gravity work underground?
Would the effect of gravity on me change if I were to dig a very deep hole and stand in it? If so, how would it change? Am I more likely to be pulled downwards, or pulled towards the edges of the hole?...
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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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Is it possible to send all nuclear waste on Earth to the Sun?
If we neglect the danger of unsuccessful lift-off of the rocket and the cost, would it be physically possible to send all nuclear waste on Earth to the Sun?
Will there be an obstacle that prevents ...
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Proof that the Earth rotates?
What is the proof, without leaving the Earth, and involving only basic physics, that the earth rotates around its axis?
By basic physics I mean the physics that the early physicists must've used to ...
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Was the 2013 meteor over Russia stronger than an atomic bomb?
Reports of the Russian meteor event (2013) say that it released more energy than 20 atomic bombs of the size dropped on Hiroshima, Japan:
Scientists estimated the meteor unleashed a force 20 times ...
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Why is air not sucked off the Earth?
People said outside earth is a vacuum. But the air does not get sucked from the Earth's surface. Some said it is due to gravity and some said the speed of air molecules are not high enough to escape....
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Why can't the Earth's core melt the whole planet?
Earth core temperature is range between 4,400° Celsius (7,952°
Fahrenheit) to about 6,000° Celsius (10,800° Fahrenheit).
Source
Why can't the Earth's core melt the whole planet? In other words, what ...
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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 earth,...
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Why is a new moon not the same as a solar eclipse?
Forgive the elementary nature of this question:
Because a new moon occurs when the moon is positioned between the earth and sun, doesn't this also mean that somewhere on the Earth, a solar eclipse (...
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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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Why does the full Moon appear?
I know that the full Moon appears when Sun, Moon and Earth are in a straight line, but if we consider that they are in straight line, why is the Moon illuminated?
I mean to say that Earth should ...
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Why wouldn't the part of the Earth facing the Sun a half year before be facing away from it now at noon?
The Earth takes 24 hours to spin around its own axis and 365 days to spin around the Sun. So in approximately half a year the Earth will have spun around its axis 182.5 times.
Now take a look at the ...
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How can the Earth keep spinning with a liquid core?
In regards to the 'conservation of angular momentum' being the explanation of why celestial objects spin...
If you fill a ball or any other container with a liquid and try to spin it, you will not ...
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Why don't we feel the subtle speed change of Earth's elliptical orbit?
Earth's orbit is a slight ellipse, so to conserve momentum its speed increases when it is closest to the Sun. If the speed changes there is an acceleration. If there is an acceleration there is a ...
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If the Earth is a good conductor of electricity, why don't people get electrocuted every time they touch the Earth?
Since the Earth is a good conductor of electricity, is it safe to assume that any charge that flows down to the Earth must be redistributed into the Earth in and along all directions?
Does this also ...
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Would you be weightless at the center of the Earth?
If you could travel to the center of the Earth (or any planet), would you be weightless there?
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Why is Earth's climate so stable?
Earth wasn't always the only water-world in the solar system. Mars also appear to have started out wet
but, as conditions changed, Mars lost its oceans.
So, how has Earth managed to avoid a similar ...
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Would it matter if the Earth rotated clockwise?
In the Futurama episode "That Darn Katz!" they save the world by rotating the Earth backwards saying it shouldn't matter (which direction Earth rotates). If Earth rotated clockwise and remained in it'...
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How fast a (relatively) small black hole will consume the Earth?
This question appeared quite a time ago and was inspired, of course, by all the fuss around "LHC will destroy the Earth".
Consider a small black hole, that is somehow got inside the Earth. Under "...
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If the moon had a mirror surface, would the earth be equally illuminated as by the sun during full moon, or would it require a different mirror shape?
Suppose the apparent diameters of the sun and the moon are exactly the same (which in fact very close to the real situation). If the moon had a perfect mirror surface, would the reflected visible ...
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Why can't we feel the Earth turning?
The Earth turns with a very high velocity, around its own axis and around the Sun.
So why can't we feel that it's turning, but we can still feel earthquake.
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Why does the Earth cool at night time?
I do understand that open water and open ground cools by the means of convection — lower air takes the heat and goes up, where it cools.
But why does the Earth lose energy and where does it go? Does ...
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If a jet engine is bolted to the equator, does the Earth speed up?
If a jet engine is bolted to the equator near ground level and run with the exhaust pointing west, does the earth speed up, albeit imperceptibly? Or does the Earth's atmosphere absorb the energy of ...
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What would happen if somebody dropped a small black hole into the Earth?
Suppose we drop a small black hole, but large enough that it accumulates mass more quickly than it radiates it, into the Earth. What happens? This question has already been asked here and here, but ...
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Build a ring around Earth, then remove the supports
What would happen if we decided to build a giant ring that managed to wrap around the whole world, end to end that was supported with pillars all along the ring and then the supports all suddenly ...
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Why doesn't Earth's atmosphere form bands due to different rotational speeds?
If the Earth's atmosphere is rotating at the same speed as Earth, then the atmosphere must be rotating much faster at the equator than at the poles. If you spin a ball covered in oil, it will form ...
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How long until we fall into the Sun?
As a planet moves through the solar system, a bow shock is formed as the solar wind is decelerated by the magnetic field of the planet. Presumably the creation of this shock wave would cause drag on ...
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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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Is the speed of Earth's spinning constant over a given 24 hours?
Is the speed that the Earth spins on its axis constant over the course of 24 hours?
As opposed to does it turn faster and slower during different hours over any given day even by a very small ...
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How much additional mass does the Earth gain each day from solar radiation?
According to this answer, energy has some (minimal) mass associated with it. Therefore, when lots of energy hits the earth (such as solar radiation in a 24 hour period) shouldn't the earth gain some ...
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How fast is the Earth-Sun distance changing
This is inspired by Evidence that the Solar System is expanding like the Universe?, which referenced an article by G. A. Krasinsky and V. A. Brumberg, "Secular Increase of Astronomical Unit from ...
user10851
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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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Why is climate change triggering faster rotation?
On July the 29th 2022, the Earth finished its rotation about 1.5 milliseconds earlier than the entire 24 hours. Scientists link this to climate change, saying that a possible reason could be due to ...
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Can helium disappear from Earth?
Helium is lighter than air, so it should fly off from Earth.
Is it possible that in the future we will run out helium?
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What is the scientific explanation for radio waves bending around the Earth?
The experiment
This experiment is documented in a documentary called Convex Earth. The exact location the following information is taken from starts at 14:25.
High frequency directional antennas are ...
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Why is the South Pole Telescope located exactly at the South Pole?
I read that there is less atmospheric interference for the telescope at the South Pole because the atmosphere is thin and there is less water vapor in the air. However this seems to be true for many ...
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Why the electric potential of Earth is zero?
For a localized charge distribution the potential is set to zero far away from the charge distribution (at infinity)
Now, when grounding a conductor, i.e. connecting it to Earth, it is said that we ...
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Finding how much time it takes for a complete Earth revolution around the Sun
Long story short, my brother made a joke about how stupid it is to celebrate the Earth making one "trip" around the Sun: New Year's Eve.
So I got curious and was wondering: how could the first ...
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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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How quickly was the Earth rotating 250 million years ago?
The Earth is slowing at a rate of $4.7\times10^{-4}$ miles per second every 100 years due to tidal forces of the moon.
See:
http://en.wikipedia.org/wiki/Earth%27s_rotation
http://imagine.gsfc.nasa....
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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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Would a giant ball on earth roll towards the poles?
The radius of the earth is higher at the equator than at the pole. Would it mean then, that if I put a giant ball at the equator, it would roll up towards the pole? Why, why not?
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If the tidal bulge on the earth speeds the moon up, how does the moon move to a higher orbit?
I understand that the moon causes a tidal bulge on Earth, and this tidal bulge moves slightly ahead of the moon due to Earth's rotation.
When reading about why the moon is moving away from the Earth, ...
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Why is Earth's gravity stronger at the poles?
Many sources state that the Earth's gravity is stronger at the poles than the equator for two reasons:
The centrifugal "force" cancels out the gravitational force minimally, more so at the equator ...
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Are the air particles in today's wind on earth (more or less) the same as the air 2/3 billion years ago?
So the air pressure on earth remains relatively constant, right?
Is there air gained or lost through transitions of any sort? e.g. plumes going out into space, earth gaining new air particles with ...
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