Principle of Liquid Pressure

Liquid pressure refers to the pressure generated inside a stationary liquid due to its own gravity. In the mid-17th century, French scientist Blaise Pascal established the basic law of pressure transmission in liquids through experimental research, known as Pascal's law. The calculation formula is P=ρ gh, where P is pressure, ρ is liquid density, g is gravitational acceleration, and h is depth. When the density of a liquid remains constant with the acceleration of gravity, the pressure of the liquid is proportional to its depth, meaning that the greater the depth, the greater the pressure. Based on this principle, when bubbles in a liquid column rise from deep within, their volume gradually increases due to the decreasing pressure exerted by the surrounding liquid on them. In the field of engineering, hydraulic systems utilize liquid to transmit pressure, enabling precise control and powerful power output. Pascal's law, proposed by Pascal, laid an important theoretical foundation for the design of various hydraulic machinery, and he is therefore known as the "father of hydraulic presses".

The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

The core scientific principle of this exhibit revolves around liquid pressure, which refers to the vertical force acting on a unit area at a point in a stationary fluid. The international unit of measurement is Pascal (Pa, 1Pa=1N/m ²). The basic law is that there is pressure inside the liquid in all directions, and the same type of liquid has equal pressure in all directions at the same depth, which is isotropic (reflected as stress tensor spherical symmetry); At the same time, liquid pressure has a significant depth dependence, increasing with depth. For homogeneous incompressible fluids, pressure calculation follows the formula p=ρ gh (where ρ is the liquid density, in kg/m ³); G is the acceleration due to gravity, with a value of 9.81m/s ²; H is the height of the liquid column, measured in meters. The pressure generated by different liquids at the same depth is related to the density of the liquid. The higher the density, the greater the pressure. For example, for freshwater (ρ=1000 kg/m ³), for every 10 meters of depth, the pressure increases by 98.1 kPa.