The experiments of French scientists show us evidence of the Earth s rotation

In order to prove that the earth is rotating, the French physicist Foucault (1819-1868) made a successful swing experiment in 1851, from which the Foucault pendulum got its name. The experiment was carried out in a domed building in Paris, France, with a pendulum length of 67 meters, a pendulum weight of 28 kilograms, and suspension points specially designed to reduce friction to a minimum. This pendulum has a large inertia and momentum, so it is basically not affected by the rotation of the earth and oscillates on its own, and the oscillation time is very long.

In the Foucault pendulum experiment, it is seen that the swing plane slowly rotates in a clockwise direction during the swing, and the swing direction is constantly changing. According to the law of inertia, the spatial direction of the swing does not change, so it can be seen that the change in the direction of the swing direction is the result of the rotation of the earth where the observer is located in the counterclockwise direction, and the observer on the earth sees the relative motion phenomenon, thus strongly proving that the earth is rotating. The position of the Foucault pendulum is different, and the swing situation is also different.

In the Northern Hemisphere, the oscillating plane rotates clockwise; In the Southern Hemisphere, the oscillating plane rotates counterclockwise, and the higher the latitude, the faster the rotation; The pendulum at the equator barely turns. The angle of deflection of the plane of the Foucault pendulum swing can be found using the formula °=15tsin in degrees. where represents the local geographic latitude, t is the time taken for the deflection, and is measured in hours, because 1 hour is equal to 15°, so for conversion, multiply by 15 in the formula.

There is also a huge Foucault pendulum in the lobby of the Beijing Planetarium, which reminds people that the earth is rotating from west to east.

The stars, the sun and the moon rise in the east and set in the west, and after the day is the night, we all know that the reason for these phenomena is because the earth is rotating, but we stand on the earth and do not feel that the earth is rotating, so how do scientists prove that the earth is rotating?

Five times prove that the earth is rotating.

Foucault's experiments proved that the clockwise movement of the direction of the swing occurs because the Earth in which the observer is located is moving counterclockwise. The direction of movement of the pendulum needle is clockwise in the northern hemisphere, counterclockwise in the southern hemisphere, and does not rotate in the direction of oscillation at the equator. The higher the latitude, the faster it moves.

At 49 degrees north latitude, where Paris is located, it takes an hour to move a week; At the South and North Poles, it takes 24 hours for the pendulum to move around for one week, which is exactly the time it takes for the Earth to rotate around one week.

It was not until 1851 that the French physicist Foucault first experimentally proved the rotation of the earth. He installed a 67-meter-long pendulum in the dome of Les Invalides in Paris, with a slender needle at the bottom of the pendulum and a sand table under the pendulum pin.

According to Foucault's experiment, according to the principle of inertia, the pendulum needle should always swing back and forth in a fixed direction without external force. However, people can see that the pendulum needle marks on the sand table, and these traces move slowly in a clockwise direction.

Five times prove that the earth is rotating.

People didn't know whether the earth rotated, but in the 16th century, Copernicus discovered that when calculating the position of the planets, it was more convenient to assume that the earth rotates once a day than to assume that the earth does not move and the whole sky rotates, so everyone accepted the idea that the earth rotates. But this acceptance is not really known, because it is not supported by evidence.

The real experimental proof of the earth's rotation was not until 1851, when the French physicist Foucault (1819-1868) did the Foucault pendulum experiment. He made a huge pendulum and made it swing, and found that the traces drawn on the sand table below the pendulum slowly changed direction, indicating that the swing plane was rotating relative to the ground, and according to the principle of conservation of momentum, the position of the swing plane in space was unchanged, so it proved that the earth itself was rotating. Since then, people have truly known that the earth has a rotation. /

The shadow of the sunlight shining into the room proves that the earth rotates. Looking at the shadows for a few days in a row and marking them at the same time proves that the earth is revolving.

The question is simple. When you're in the shower, do you see if the water is flowing backwards or in the hole.

I'd like to ask about this assignment.

Methods of proving the rotation of the Earth:

1.Toothpick method.

First fill a basin with water, put it in a horizontal and non-vibrating place, after the water is still, gently put down a thin wooden toothpick, and make a mark at one end of the toothpick, remember the position of the toothpick, after a few hours (preferably more than 10 hours), when you look again, you will find that the toothpick has rotated at a certain angle, it looks like the toothpick is rotating, in fact, it is not rotating, but the earth is rotating. In the Northern Hemisphere, the toothpick rotates clockwise because the Earth's rotation appears counterclockwise in the Northern Hemisphere. The Southern Hemisphere is the opposite of the Northern Hemisphere.

2.Cannonball method.

The earth is constantly rotating, and objects moving horizontally on the ground must have a continuous deviation to the right (northern hemisphere) or left (southern hemisphere).Based on this phenomenon, one can prove that the earth is rotating by analyzing the direction of the movement of the projectiles.

3.Gravitational acceleration method.

The earth rotates constantly at all times, and due to the action of inertial centrifugal force, the gravitational acceleration of the ground must be the smallest at the equator and the largest at the poles; The Earth cannot be a positive sphere, but must be a spheroid with a slightly bulging equator and slightly flattened poles. The results of gravity measurements and radian measurements confirm the correctness of these views, which also confirms the rotation of the earth from one side.

4.Deep well measurements.

The earth is constantly rotating, because the rotation speed increases with the height, the object must have a high eastward rotation speed in the process of falling from a height, and it will inevitably fall to the easterly location. To confirm this, tests were carried out in very deep mines. The results of the test were:

The object falling from the center of the wellhead always collides with the east wall of the mine at a certain depth, confirming the rotational motion of the earth from another side.