What do the tides and tides in tides represent

Tide: The rise and fall of the sea. (Early period).

Tide: Evening tide.

Tidal refers to high tide, and tidal refers to low tide.

Tides are related to the gravitational pull between the Moon and the Sun on the Earth. Tide refers to the periodic movement of seawater under the gravitational force of celestial bodies (mainly the moon and the sun), and is a phenomenon of periodic fluctuations and fluctuations of seawater formed under the gravitational force of the moon and the sun.

The elastic-plastic deformation of the solid earth caused by the gravitational force of the sun and the moon is called the solid tide, referred to as the solid tide or ground tide. The periodic rise, fall, advance and retreat of the sea surface caused by the gravitational force of the sun and the moon are called ocean tides, referred to as ocean tides.

The Moon is closer to the Earth than the Sun, and the ratio of the gravitational force of the Moon to the Sun is 11:5. For the oceans, the solar tides are more pronounced than the solar tides. The driving force of earth tides, ocean tides and air tides is caused by the different gravitational forces of the sun and the moon on various parts of the earth, and the three affect each other.

The tidal phenomenon is dominated by the moon, and the summer calendar, which is based on the changes in the phases of the moon, is a guide to maritime activities in ancient times. The Moon is attractive to the Earth's seawater, and the points on the Earth's surface are different from the Moon, and the place facing the Moon is gravitationally strong, and the seawater expands outward; The place with the back to the moon is less gravitational, and the centrifugal force becomes larger, and the sea water expands to the place with the back to the moon under the action of centrifugal force, and the tide will also occur.

Tides have two high tides and two small tides in a month, with the high tide period being the first and fifteenth day of each month; The low tide period is on the 7th and 22nd of each month.

On the New Year's Day, the Sun, the Moon, the Sun and the Earth are almost in a straight line, and the tides caused by the Moon and the solar energy are superimposed on each other, so that the sea surface rises and falls greatly, so it is called "big tide".

In fact, due to other factors, the tide does not necessarily occur on the new day, but may be delayed by two or three days. Due to the influence of other factors (such as seawater friction, inertia, shoreline contour and seabed topography, etc.), the date of occurrence of high tides is not on the new day or the sun, and is often delayed by 2 or 3 days.

World celebrities

The Qiantang River tide is one of the three major tides in the world, which is caused by the centrifugal action of celestial gravity and the rotation of the earth, coupled with the special topography of the horn mouth of Hangzhou Bay. The Qiantang River Estuary is wide on the outside and narrow on the inside, and is in the shape of an obvious trumpet. The river at the mouth of the river is 100 kilometers wide, and the further you go, the narrower the river becomes, and when you reach the area of Yanguan Town, Haining, the river level drops sharply to only 3 kilometers wide.

The tide of the Qiantang River and the tide of the Yangtze River, which penetrates more than 600 kilometers inland. It is mainly formed by the fact that the tidal currents are traced up the course of the rivers that flow into the sea. The tide rushes into the triangular bay, the tide level is piled up, and the tidal range increases.

When the tide comes, the tide end is steep, the water splashes in all directions, like a high-speed vertical water wall, the front has not been dredged, and the waves behind catch up, wave after wave, very spectacular, form"The monstrous turbidity waves emptied, and the rivers and mountains were destroyed"A spectacular sight.

Yu Yafei Shiyun: "Qiantang looks at the waves, and the tide is in front of you in an instant; It seems that in the ordinary river water, the energy contained can be shocking." At the beginning of the tide, a white line flashed on the river surface, accompanied by a rumbling sound, the tide head came from far and near, galloping, the tide head pushed, the sound was like thunder, in an instant, the tide peak rose a water wall three or four meters high and stood upright on the river surface, spraying beads and splashing jade, the momentum was like ten thousand horses galloping.

Tide watching began in the Han and Wei dynasties, flourished in the Tang and Song dynasties, and has become a local custom after more than 2,000 years.

Question 1: What does tidal mean It is an astronomical phenomenon in which the earth receives the gravitational pull of the sun or the moon, causing the earth's water to occur regularly ** or fall.

Question 2: What are the tides? Tidal phenomena refer to the periodic movement of sea water under the action of celestial gravitational forces, and it is customary to call the vertical rise and fall of the sea surface tide, and the flow of sea water in the horizontal direction is called tidal current.

In ancient times, the water gushing from the river and sea during the day was called "tide", and the water at night was called "tide", which was collectively called "tide".

Question 3: What is a tide? When does the sea rise and fall tidal phenomena refer to the periodic movement of sea water under the action of the gravitational force of celestial bodies (mainly the moon and the sun), it is customary to call the vertical rise and fall of the sea surface tide, and the flow of sea water in the horizontal direction is called tidal current.

It is a natural phenomenon in coastal areas, in ancient times, the water gushing from the river and the sea during the day was called "tide", and the water at night was called "tide", which was collectively called "tide".

Question 4: What does tide mean Tide is a natural phenomenon in coastal areas, which refers to the periodic movement of sea water under the action of the gravitational force of celestial bodies (mainly the moon and the sun). In order to indicate the moment of the tide, our ancestors called the tide that occurred in the morning and the tide that occurred at night.

This is the origin of the name of the tide.

Under the gravitational pull of the Moon and the Sun, the water surface of the ocean periodically fluctuates. The tides are weighed during the day and the tides at night, which are collectively called "tides". Generally, it rises and falls twice a day, and there are also fluctuations once.

The tidal waves of the open sea are traced up the river, and the tide occurs in the lower reaches of the river. Northern Qi Yan Zhitui "Yan's Family Motto Returning to the Heart": "The tide goes back, who will save it?" ”