Pascal's law

[4] The law was established by French mathematician Blaise Pascal in 1653 and published in 1663.

[5][6] Pascal's principle is defined as: A change in pressure at any point in an enclosed incompressible fluid at rest is transmitted equally and undiminished to all points in all directions throughout the fluid, and the force due to the pressure acts at right angles to the enclosing walls.For a fluid column in a uniform gravity (e.g. in a hydraulic press), this principle can be stated mathematically as:

Alternatively, the result can be interpreted as a pressure change caused by the change of potential energy per unit volume of the liquid due to the existence of the gravitational field.

[further explanation needed] Note that the variation with height does not depend on any additional pressures.

The formula is a specific case of Navier–Stokes equations without inertia and viscosity terms.

), an additional pressure due to the weight of the load is transmitted throughout the liquid and up against the right piston.

The hydraulic press does not violate energy conservation, because a decrease in distance moved compensates for the increase in force.

The input force multiplied by the distance moved by the smaller piston is equal to the output force multiplied by the distance moved by the larger piston; this is one more example of a simple machine operating on the same principle as a mechanical lever.

A typical application of Pascal's principle for gases and liquids is the automobile lift seen in many service stations (the hydraulic jack).

The oil, in turn, transmits the pressure to a piston, which lifts the automobile.

Hydraulics is employed by modern devices ranging from very small to enormous.

For example, there are hydraulic pistons in almost all construction machines where heavy loads are involved.

[9] In the experiment, Pascal supposedly inserted a long vertical tube into an (otherwise sealed) barrel filled with water.

When water was poured into the vertical tube, the increase in hydrostatic pressure caused the barrel to burst.

: "barrel-buster");[10] nevertheless the experiment remains associated with Pascal in many elementary physics textbooks.