1 MPa means that the pressure on 1 cm2 is 10 kg, or a force of 0. 1 kg acts on 1 mm2. That is, 1mpa = 10kg force/cm2 = 0.1kgf /mm2 = 1N/ mm2. As a unit of pressure, Pa is also the name of a scientist. Pascal is a famous French mathematician, physicist, philosopher and essayist.

Pascal put forward a law about liquid pressure, which was later called Pascal's law. The principle of intuitionism he established had an influence on some later philosophers, such as Rousseau and Bergson. Pascal died on August 9, 662 at the age of 39. Later generations named the pressure unit Pa after Pascal.

Stress experiment:

Pascal made a famous experiment in 1648. He used a closed bucket filled with water, inserted a slender tube into the lid of the bucket, and poured water into the slender tube from the balcony of the building. As a result, only one glass of water was used, and the bucket cracked, and the water in the bucket flowed out of the crack. It turned out that because the small tube is small, pouring a glass of water into it is also very deep.

Because the pressure of liquid is equal to the product of density, depth and gravitational acceleration constant. In this experiment, the density of water is constant, but the depth increases again and again, so the pressure in the lower part is getting bigger and bigger, and its water pressure finally exceeds the upper limit that the barrel can bear, and the barrel cracks. Pascal's barrel crack experiment can well prove that the liquid pressure is related to the depth of the liquid, but not to the quality of the liquid.