<h1 class = "pgc-h-arrow-right" > first concludes that the water on Earth rises and falls as much, or in the large basin of the ocean. </h1>
The rising tide and the low tide are not extra water, but the water in a basin is high here, it is low there, it falls back here, it rises again, so that it tosses back and forth.
So where the tide came from, or where it went.
The Earth is a large sphere with a diameter of 12,756 kilometers, which is composed of several layers, namely the atmosphere, the hydrosphere, the crust, the mantle, and the core.
Hydrospheres are the rivers, lakes and seas that occupy 71% of the earth's crust, mainly the ocean. Earth's gravity holds this water firmly attached to the earth's crust.
However, the earth is rotating, affected by the gravitational attraction of celestial bodies such as the moon and the sun, which is doomed to these waters can not stay calm and calm, and will inevitably rise and fall in waves.
< h1 class="pgc-h-arrow-right" > ebb and flow is the result of the Earth's rotation and gravitational perturbation. </h1>
Gravity is one of the four most basic forces in our world, which fill every corner of the universe and have a gravitational effect between any object.
Our earth is held back by the gravitational pull of the sun and has to orbit the sun; and the moon, which in turn is held by the gravity of the earth, has to orbit the earth.
These gravitational pulls are bound to have an effect on objects on Earth.
The law of gravitation is expressed as: F=GMm/r^2
where F represents the gravitational magnitude value and G is the gravitational constant, which is approximately equal to 6.67x10^-11N·m^2/kg^2; M and m are the masses of the two interacting objects; r is the distance between the particles of the object.
This law states that the magnitude of gravity is proportional to the mass product between objects and inversely proportional to the square of the distance. That is to say, the closer the distance, the greater the gravitational force, and the farther the distance, the gravitational force will decay exponentially.
Therefore, although the gravitational pull of the sun is large, people and various objects are still firmly attracted to the surface of the earth because they are too close to the earth; in the same way, because the sun is 150 million kilometers away from the earth, and the moon is on average 384,000 kilometers away from the earth, the gravitational interaction between the earth and the moon is more obvious than that of the sun.
<h1 class= "pgc-h-arrow-right" > gravity derives the tidal force, which is the root cause of the ebb and flow. </h1>
Gravity is manifested as a pulling force on the object as a whole, while the tidal force is the pulling force derived from gravity on different parts of the object.
The planet is a circle, and the gravitational force will have a distance difference when it falls on different parts of the planet, so the gravitational force is different, which is the tidal force.
The magnitude of the tidal force is somewhat different from the gravitational force, and the relationship with distance is more sensitive and close.
Ebb/ebb Official: F1=GMm/r^3
Where f1 is the value of the induced force, G is the gravitational constant, M and m are the mass of the object with the force of the tidal force, and r is the distance between the objects acting on the tidal force.
As can be seen from the formula, the tidal force is relative to gravity, the distance decays more severely, and it decays in a cubic exponent.
Therefore, at a great distance, the moisture attraction between celestial bodies is not obvious, and as the distance is closer, it becomes more and more severe, even extreme.
<h1 class= "pgc-h-arrow-right" > the extreme tipping point of the tidal force is called the "Roche limit". </h1>
The so-called "Roche Limit" is that when two celestial bodies are close to a critical point, the moisture force will tear one celestial body to pieces.
The study believes that Saturn's rings are composed of pieces that are torn apart by Saturn's tidal force when a small object approaches Saturn to reach the "Roche Limit".
The tidal force is actually under the total gravitational force, showing different pulling forces on different parts of the planet, making the planet deform.
The Earth's tidal force on the moon originally had this effect, but because the moon is a rocky rigid body shell, the deformation caused by the tidal force is not obvious, except for measurements with precision instruments, the human eye can not see.
The Earth-Moon distance from the Rigid Body Roche Limit is 9495665 meters, the fluid Roche Limit distance is 18261459 meters, and the actual Earth-Moon distance from the Roche Limit is very far, so the Earth's moisture attraction will not cause damage to the Lunar Rigid Body Shell.
Gravity is mutual, the moon of course also has a tidal force on the earth, and the earth's atmosphere and hydrosphere are fluids, and the deformation caused by the tide force is obvious.
Therefore, the high tide and low tide are the deformation caused by the moisture attraction force.
In fact, the tide rises and falls not only the water, but also the atmosphere, which is not to be said here.
< h1 class = "pgc-h-arrow-right" > Earth's ebb and flow is mainly influenced by the Moon. </h1>
The Moon is much closer to Earth than the Sun, about one-third of the distance the Sun is from Earth.
According to the attenuation of the tidal force by the distance cube, the lunar moisture attraction force is more than the sun, and it has been estimated that the lunar gravitational tide is 2.2 times that of the sun.
Due to the rotation of the earth, when the place is facing the moon, the water in that place is pulled up by the moon's moisture pull, while the other places that are not facing the tide force is relatively small and will flow in the direction of the large tide force.
In this way, the tide will rise where the moon is facing, the sea will rise higher, and the water on both sides of the earth that is not facing will go down and become a falling tide.
< h1 class = "pgc-h-arrow-right" > why does the other side of the Earth with its back to the moon also have a high tide? </h1>
It turns out that the other side of the earth facing the moon has become the smallest due to gravity, the pulling force on the sea water is small, and the centrifugal force of the earth's rotation will shake the water up, which will also show the same tide phenomenon.
The earth rotates once a day, so that there are two high and low tides in each sea. But since the Moon also orbits the Earth, this complex mechanism of operation is less accurate twice a day.
Therefore, the earth's high tide and low tide are mainly affected by the moon's tidal force, which is a kind of up-and-down phenomenon, water or those waters, they are in the ocean this big basin of self-congratulation.
<h1 class="pgc-h-arrow-right" > in addition to the Moon, the Sun and other planets also have certain tidal effects on Earth. </h1>
Although the sun's tidal force on the earth is not as large as that of the moon, its impact is still relatively obvious.
This effect is most pronounced when the Sun is in a straight line with the Moon and the Earth, and when it is in a triangular position.
When there is no moon on the 15th full moon of the lunar calendar and the first day of the first month, the sun and the moon and the earth are basically in the same line, this time is the superposition of the tide force of the sun and the moon, and it is the time when the tide is the greatest, called the big tide.
The time of watching the tide in the world is basically around this period, such as the Qiantang tide.
At the beginning of the seventh and eighth lunar calendar and the twenty-second and twenty-third hours, the moon runs to a triangular position with the earth and the sun, at this time, the tidal force of the moon and the sun on the earth is pulled and dispersed by each other, so it is the time when the tide is the smallest, called the small tide.
This is also the most useful place for the lunar calendar, because the lunar calendar is originally set according to the moon.
Planets such as Mars, Jupiter, and Venus also have a certain amount of moisture attraction on the Earth, but the impact is relatively small and is generally ignored.
The Moon accounts for about 68% of the tidal force to earth, about 31.4% of the Sun, and about 0.6% of the rest of the planets combined.
This is where the tides come from and how they come about.
Thanks for reading and welcome to discuss.
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