First year of secondary education
Pressure (I)
E. Vallo - J.Villasuso
 Pressure
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Hydraulic press 2 / 3

If you exert a force F1 on the small piston with a cross section S1, you create a pressure P in the liquid under the small piston with the value F1 / S1. This same pressure P is manifested in all the fluid mass, and exerts on the large piston with cross section S2 a force F2 so that:

That is, the force that the liquid exerts on the large piston is F2.

The force that the press exerts (F2) is the force that you have exerted (F1) multiplied by the relationship between the surface areas of the pistons (S2 / S1). If the surface of the large piston is double that of the small piston, the force exerted by the press is double that which you exerted, if the relation is triple, the force is triple, etc.

 

There shouldn't be any gas between the pistons and the liquid. The gas is compressible and the hydraulic press is based on a property of incompressible liquids.
Why doesn't the hydraulic press, in spite of multiplying the force we apply by a factor, also increase the amount of work?

What is pressure? How does it work?
Units
Hydrostatic pressure
Mathematical expression
The pressure increases the deeper you go in liquids
Which goes the furthest?
A little goes a long way!
Communicating vessels
Syphons
Pascal's Law
The Law
The hydraulic press
Hydraulic brakes: drum brakes
Manometers
Problems
Evaluation