Main contribution

It can be divided into the following three aspects:

① mechanics

Galileo was the first scientist to introduce experiments into mechanics.

He determined some important mechanics through the combination of experiment and mathematics.

Law. 1582, after long-term experimental observation and mathematical calculation,

The isochronous law of pendulum is obtained. Then at 1585, due to family financial difficulties,

Drop out of school When he left the University of Pisa, he made an in-depth study of the ancient Greek scholar Ogi.

The works of Reid, Archimedes and others. According to the lever principle and buoyancy principle.

Richard wrote his first paper entitled "Balance". I wrote another paper soon.

On gravity reveals the essence of gravity and center of gravity for the first time, and gives its accuracy.

Precise mathematical expression, so it is famous. At the same time, he told Ali

Many of stoddard's views are questioned.

From-1589 to1591year, Galileo made a detailed study on the motion of falling bodies.

Observe. Aristotle, who has ruled for thousands of years, has been denied both experimentally and theoretically.

Regarding the "law of falling body motion", the correct "law of free falling body" is established.

That is, balls with different weights fall at the same time when air resistance is ignored.

The speed of landing and falling has nothing to do with weight. According to Galileo's late student,

According to V. viviani's records, the falling experiment was conducted in public on the leaning tower of Pisa.

Yes, but Galileo didn't explicitly say that the experiment was in Pisa.

On the tower. So it has been controversial for several years.

-Basic concepts of Galileo's motion, including center of gravity, speed and acceleration.

They all made a detailed study and gave strict mathematical expressions. special

The concept of acceleration is a milestone in the history of mechanics. With the addition

The concept of speed, the dynamic part of mechanics, can be based on science.

Above, and before Galileo, only the statics part was described quantitatively.

Galileo informally put forward the law of inertia (see Newton's motion)

Law) and the law of motion of objects under the action of external forces, which was formally put forward by Newton.

The first and second laws of motion laid the foundation. On the basis of classical mechanics,

Galileo was a pioneer of Newton.

Galileo also put forward the law of resultant force, projectile motion's law, indeed.

Galileo's principle of relativity was established.

Galileo's contribution to mechanics is various. This was in his later years.

Written mechanical work "Talk and mathematical proof about two new sciences"

This is described in detail in. In this immortal book, in addition to dynamics, but also

There is a lot of knowledge about mechanics of materials. For example, he elaborated on light beams.

Bending test and theoretical analysis correctly determine the bending capacity and geometric shape of the beam.

Mechanical similarity relation of dimensions. He pointed out that for cylindrical beams with similar lengths,

The bending moment is proportional to the cube of radius. He also analyzed the concentrated load.

Simply supported beam correctly points out that the maximum bending moment is under load, and it reaches two points with it.

Proportional to the product of distance. Galileo also applied the theory of beam bending to practice.

This paper analyzes the problems that should be paid attention to, and points out that it should not exceed the size of engineering structure.

Big, because they will be destroyed by their own weight. He is honest.

It has been found that when the size of an animal decreases, its physical strength is not proportional.

Reduce. He said, "A puppy may be able to carry two or three cats."

The size of a dog, but I believe a horse may even be as big as it.

You can't even afford a horse. "

② Astronomy

He has made many achievements in observing celestial bodies through telescopes.

The first scientist. These achievements include: it is found that the surface of the moon is uneven.

Ping, Jupiter has four satellites (now called Galileo satellites), sunspots and

The rotation of the sun, the profit and loss phenomenon of Venus and Jupiter, the Milky Way.

Star composition, etc. He completely confirmed Copernicus's "ground motion theory" with experiments.

Denied Aristotle and Ptolemy's "theory of celestial movement" which ruled for more than 1000 years.

③ Philosophy

He insisted on idealism and scholasticism of the church all his life.

Struggle advocates using concrete experiments to understand the laws of nature and thinks that experience is rational.

On the source of knowledge. He denied the existence of absolute truth and the mastery of truth in the world.

Absolute authority, against blind superstition. He acknowledged the objectivity and diversity of matter.

Similarity and infinity of the universe are of great significance to the development of materialist philosophy.

It means a lot. However, due to historical limitations, he emphasized that only

Material attributes summarized as quantitative characteristics exist objectively.