Blaise Pascal (1623-1662) was a famous physicist and talented mathematician in the 17th century. We know that there is Pascal's law of liquid pressure in physics, and Pascal has made extraordinary achievements in mathematics.
Pascal is famous as a theologian. He is the founder of the mathematical theory of probability. This kind of research starts with the discussion about gambling opportunities, which is of great practical significance to science, philosophy and social statistics.
Pascal was born on June 19th, 1623 in Clermont-Ferrand, France. His father is a very talented mathematician, which provides a good family environment for Pascal's growth. Pascal was very interested in mathematics. In 164, he published a paper on conic curves and put forward the basic theorem of projective geometry.
Pascal was weak and sick since childhood, but he was intelligent, intelligent and diligent. He lived only 39 years old, but he became a scientist, philosopher and writer. His Letters to the Outsiders and Records of Thoughts, with rigorous and beautiful language and beautiful and profound thoughts, have become masterpieces of French literature.
discover Pascal's theorem
Pascal put forward Pascal's theorem in mathematics when he was 16-17 years old.
Girard Desargues, a French mathematician born in 1591, began to study projective geometry since Apolloni studied conic curves in ancient Greece. The second person who contributed to projective geometry was Pascal.
From the age of 13, my father often took Pascal to attend the regular meeting of Mei Sen College in France, which was the predecessor of French Academy of Sciences. Pascal could understand Mei Sen's speech and was appreciated and helped by Girard Desargues.
in p>164, Pascal published a paper on conic curve, which led to more than 4 inferences, put forward the basic theorem of projective geometry called the mysterious hexagon by Girard Desargues, and made the most important research on conic curve since Apolloni.
This geometric theorem named after Pascal is very concise; If a hexagon is inscribed on a circle (more generally a conic curve), every two opposite sides intersect to get three points, which are on the same straight line.
it can also be said that if the lines of three pairs of opposite sides inscribed with a hexagon intersect respectively, then the three intersections must be * * * lines.
Mathematical historians believe that this theorem alone is enough to make Pascal immortal. Indeed, Pascal was just sixteen or seventeen at this time. When Descartes, a famous mathematician at that time, read the paper, he couldn't believe that such an important theorem came from a teenager. He shook his head and said, "A 17-year-old boy won't find this theorem!"
Pascal's work initiated the study of projective geometry and created the preparatory conditions for the birth of calculus. Leibniz, a famous German mathematician and one of the founders of calculus, said, "When I read Pascal's works, I suddenly realized the truth like an electric shock."
in p>1642, Pascal, aged 19, also invented a gear computer which can do addition and subtraction, and obtained a patent. This is the world's first mechanical computer.
Pascal and Air Pressure and Hydraulic Pressure
In physics, the unit of atmospheric pressure is named "Pa", which is to commemorate the genius physicist Pascal.
Pascal is not only a genius in physics, but also a real genius in mathematics. Here, let's talk about his research on atmospheric pressure first.
in p>1646, the French physicist Pascal was interested in the atmospheric pressure experiment of the Italian physicist Torricelli and began to study atmospheric pressure. He thought, "vacuum is not impossible in nature, and nature does not avoid vacuum with such great disgust as many people imagine."
Pascal came up with an experiment to bring a mercury barometer to the top of the mountain. Compared with the bottom of the mountain, the mercury column should be lower. He was in poor health and entrusted his cousin to take Torricelli's mercury instrument to the local Dom Mountain. Sure enough, at a height of 1 mile, the mercury column dropped by 3 inches. This experiment is repeated, which strongly supports Pascal's view on atmospheric pressure.
Pascal made an important discovery on the pressure of liquid. He found that the pressure acting in a sealed liquid can be completely transferred to any place inside the liquid and vertically act on any interface it touches. This is the famous Pascal principle, that is, Pascal's law.
in p>1647, Pascal made a wonderful experiment. He made a large wooden barrel, which was well sealed and watertight. He made a small hole in the lid of the big barrel and inserted a 13-meter-long thin tube into the hole. After all this was done, he carried the barrel outside and put it under the house.
Then Pascal climbed up the roof with a ladder, which was already crowded with onlookers. Pascal said to everyone, "here we are going to do an experiment to see how much pressure water can produce, which is also to prove one of my findings."
in a short time, the bucket was filled with water. Pascal held the kettle in his hand and said to everyone, "I'm going to fill the small tube now, because the barrel is full, so the water in the small tube will be filled higher and higher. This small pot of water in my hand is not heavy, even a child can lift it, but once it is pulled into a thin and high water column, it will have unexpected effects."
Pascal let the water in the pot flow slowly down the thin tube. Just after a while, the water in the pot was not finished, but there was a crack with a bang. The big barrel was pushed open and the water was spouting. People were all surprised and speechless. What a surprise! There will be so much pressure!
Pascal explained that the barrel broke because the water in the thin tube gave pressure to the water in the barrel, and this pressure was transmitted by the water to the inner wall of the barrel in all directions. Therefore, if two containers with different cross-sectional areas are connected together, for example, a thin tube is connected to a wooden bucket, and a small pressure is exerted on a small cross-section, a great pressure will be generated on a large cross-section, because the liquid transmits pressure.
Pascal also found that the hydraulic press is a lever, and the product of force and arm remains unchanged. In a hydraulic press composed of two pistons, the bigger the piston, the smaller the height change of the liquid and the greater the force it receives.
in p>1648, Pascal published an important experimental report on liquid equilibrium. After his death, he published On Liquid Balance and Pressure of Gaseous Substances.