Pascal’s law states that

A small force (F_{1}) is applied to piston with a small area (A_{1}) produces a much large force F_{2} on the larger piston. It is schematically illustrated in figure. A well known **application of Pascal’s law** is the hydraulic lift is used to support or lift heavy objects.

A piston with small cross section area A_{1}, exerts a force F_{1} on the surface of a liquid such as oil. The applied pressure P = F_{1} / A_{1} is transmitted through connecting pipe to a larger piston of area A_{2}.

The applied pressure is the same in both cylinders, so

Where, P = pressure (Pa or N/m^{2})

F = force (N)

A = area (m^{2})

In the above figure **A _{2} > A_{1}**, therefore,

**F**.

_{2}> F_{1}Thus, hydraulic life is a force multiplying device with multiplication factor equal to the ratio of the areas of the two pistons. dentist’s chairs, car lifts and jacks, any elevators and hydraulic brakes all use pascal’s law principle.