1MPa=10^6Pa
Pa is the unit of pressure. 1Pa is 1N/m^2. 1Pa is the pressure generated by a force of 1N uniformly pressing on an area of ??1m^2. . It is conceivable that 1Pa is a very small pressure. Directly using Pa as the unit of measurement for pressure will also cause a lot of inconvenience in the calculation of centuries, so some larger units of measurement are often used. For example, 1Mpa, 1atm, 1cm mercury.
1Mpa is 1 million times 1Pa, that is, 1Mpa=10^6Pa, or if you prefer, you can also write 1Mpa=1000000Pa. Note here 1Mpa=1 million Pa instead of 1 megapa.
Pascal (Pascal, referred to as Pa) is the unit of pressure, and it is also the name of a scientist. Pascal was a famous French mathematician, physicist, philosopher and essayist.
Pascal Blaise, French mathematician, physicist, and founder of modern probability theory. He proposed a law about liquid pressure, later known as Pascal's law. The principles of intuitionism he established had an influence on later philosophers, such as Rousseau and Bergson.
Born on June 19, 1623 in the city of Clermont-Ferrand, Mont-de-Dome, France. Pascal had no formal schooling. His mother died of illness when he was 4 years old, and his father and two sisters, who were highly educated and served as government officials, were responsible for his education and training. His father was a respected mathematician. Under his careful education, Pascal became proficient in Euclid's geometry at a very young age. He independently discovered Euclid's first 32 theorems in perfect order. correct. After discovering on his own that "the sum of the interior angles of a triangle is equal to 180 degrees" at the age of 12, he began to learn mathematics from his father. In 1631, Pascal moved to Paris with his family. His father discovered that Pascal was very promising. When he was 16 years old, he took him to participate in the academic activities of the Paris mathematicians and physicists group (the predecessor of the Paris Academy of Sciences, France), which opened his eyes. When he was 17 years old, Pascal wrote The article "The Theory of Sections of Cones" with a high level of mathematics was the result of his study of De Zalgue's classic work on synthetic projective geometry.
In 1641, Pascal moved to Rouen with his family. While helping his father with tax calculations from 1642 to 1644, Pascal invented the adding machine, the world's earliest calculator, now on display in a French museum. In 1610, he accepted religious teachings, but he was still committed to scientific experimental activities. Between 1653 and 1653, Pascal concentrated on research on vacuum and hydrostatics, and achieved a series of major results. Returned to Paris in 1647. He conducted a large number of experiments based on Torricelli's theory. The experiment in 1647 shocked the whole of Paris. He himself said: The fundamental guiding ideology of his experiments was to oppose the traditional concept that "nature abhors a vacuum". From 1647 to 1648, he published a paper on the vacuum problem. In 1648, Pascal conceived and conducted an experiment to measure atmospheric pressure at different altitudes in the same area, and discovered the law that atmospheric pressure increases as altitude decreases. In the past few years, Pascal continued to make new discoveries in experiments, and made many major inventions, such as the invention of the syringe, the hydraulic press, and the improvement of Torricelli's mercury barometer. From 1649 to 1651, Pascal and his collaborator Pierre (Perier) measured the changes in atmospheric pressure at the same location in detail and became a pioneer in using barometers for weather forecasting. In 1651, Pascal began to summarize his experimental results. In 1654, he wrote "Essays on Liquid Equilibrium and Air Weight", which was officially published in 1663. Afterwards, Pascal turned to theological studies, and in 1655 he entered the theological center of Pitre. He started from skepticism and believed that both perceptual and rational knowledge were unreliable, and thus came to the conclusion that faith is above all else.
Before 1646, the Pascal family believed in Catholicism. Due to his father's illness, he came into contact with a more profound way of religious belief, which had a great impact on his future life. Pascal corresponded with the mathematician Fermat, and together they solved a problem sent by an upper-class gambler and amateur philosopher. He couldn't figure out why he always lost money when he bet on a certain combination of three dice. In the process of solving this problem, they laid the foundation of modern probability theory. He made many contributions during his short life, with the greatest contributions in mathematics and physics. In 1646, in order to test the theories of Italian physicists Galileo and Torricelli, he made a mercury barometer and repeatedly conducted atmospheric pressure experiments on the top of Clermont-Ferrand overlooking Paris, laying the foundation for fluid dynamics and The study of hydrostatics paved the way. In the experiment, in order to improve Torricelli's pneumatic juice, he invented a syringe based on Pascal's law and created a hydraulic press. His research and writings on vacuum problems further enhanced his reputation. He has been physically weak since he was a child and has been plagued by diseases due to overwork. However, it was during his illness leave from 1651 to 1654 that he intensively carried out scientific work and wrote many papers on liquid balance, the weight and density of air, and arithmetic triangles. The latter paper became the basis of probability theory. He also wrote many religious works between 1655 and 1659.
In his later years, someone suggested that he publish the results of his research on tricycles, so he immersed himself in scientific interests. However, from February 1659, his illness worsened, making him unable to work normally and contented himself with a pious religious life. . Finally, he passed away in great pain.
Pascal died on August 19, 1662, at the age of 39. In order to commemorate Pascal, later generations named the unit of pressure after him, referred to as "Pa".
In his famous philosophical work "Thoughts", Pascal left a famous saying to the world: "Man is just a reed, the most fragile thing in nature." But he is a thoughtful reed. of reeds.
The scientific community remembers Pascal's achievements. The International System of Units stipulates that the unit of "pressure" is "Pascal" because he was the first to propose the "Pascal's law" or "Pascal's principle" to describe the properties of liquid pressure. ".
The computer field will never forget Pascal's contribution. The PASCAL language, which was launched in 1971, is also to commemorate this pioneer and keep Pascal's name in the computer age.
There is also "Pascal's theorem" in mathematics.
The following is a detailed introduction:
Pascal's achievements are multifaceted. His contributions to mathematics and physics occupy an extremely important position in the history of science.
Pascal's mathematical attainments are very profound. In addition to his outstanding contributions to probability theory and other aspects, the most outstanding one is the famous "Pascal's Theorem" - which he proposed in "A Treatise on Conic Sections". Pascal's theorem is an important theorem of projective geometry, that is, "the line of intersection of the three pairs of sides of a conic inscribed in a hexagon".
In his algebra research, he published many papers on arithmetic series and binomial coefficients, and discovered the coefficient law of binomial expansion, which is the famous "Pascal's triangle". (called "Yang Hui's triangle" in our country), he and Fermat *** jointly established the basis of probability theory and combinatorial theory, and came up with a series of solutions to problems in probability theory. He studied the cycloid problem and derived general methods for finding the areas and centers of gravity of different curves. He calculated integrals of trigonometric functions and tangents and was the first to introduce elliptic integrals.
Research Contributions
1. In 1639, he published an excellent mathematical paper "On Conic Sections";
2. His philosophical masterpieces "Thoughts";
3. Pascal discovered the law that atmospheric pressure increases with height. He not only repeated Torricelli's experiment, but also verified his own inference: since atmospheric pressure is generated by the weight of air, the liquid column in the glass tube should be shorter at higher altitudes;
4. "Letter to Foreigners";
5. In 1641, Pascal invented the adding machine;
6. "A Treatise on Conic Sections";
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7. Discover Pascal's law (in fluid (gas or liquid) mechanics, it means that the pressure change that occurs in a certain part of a stationary fluid in a closed container will be transmitted to all parts of the fluid and the pressure of the container wall without any loss. It is equal to the force divided by the area of ??action. According to Pascal's principle, applying a certain pressure on one piston in a hydraulic system will produce the same pressure increase on the other piston if the area of ??the second piston is the first. 10 times the area of ??the piston, then the force acting on the second piston will be 10 times greater than the first piston, while the pressure on the two pistons will still be equal. The hydraulic press is an example of Pascal's principle. Uses, such as hydraulic braking, etc.;
8. Pascal also discovered that the pressure at any point in a stationary fluid is equal in all directions, that is, the pressure at that point is equal on all planes passing through it. This fact Also known as Pascal's principle (law);
Einstein, Newton and Pascal's episode
There is such a joke:
Scientists after death They all went to heaven. One day, the scientists were playing hide and seek, and it was Einstein's turn to catch someone. After counting 100, he found Newton standing next to him and said, "Newton, I caught you."
"No, you are not grabbing Newton."
"Then who are you?" Einstein asked
"What do you see under my feet?" Newton. Smiling slyly.
Einstein saw that under Newton's feet was a square plank with a side length of one meter.
"I am standing on a square plank of one meter." Newton/square meter', so what you caught was not Newton, but 'Pascal'."
After Einstein heard this, he called Pascal. After hearing this, Pascal smiled and bent down to pick up Newton. The board under his feet said to Einstein: "I am Pascal now, right?" After that, he threw the board out. "There are no square meters, now I am Newton."
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