Application of Pascal’s Law in Hydraulic Jack

The hydraulic jack embodies the word “four-two-pull a thousand catties” vividly and vividly. A small jack weighs no more than a few catties to a few dozen catties, but it can lift a few tons or even hundreds of tons of heavy objects. It is really incredible. Then, what is the inside of the hydraulic jack energy?


Hydraulic jack is a product of classical physics. While we are amazed by human wisdom, it is necessary to understand the working principle of hydraulic jack. So today, I will give you a simple analysis from the perspective of physics. Hydraulic jacks.
First of all, we have to understand a classic theory in classical mechanics, that is, Pascal’s law, Pascal’s law, which is a law of hydrostatics. “Pascal’s Law” states that after any point in an incompressible static fluid generates a pressure increase due to an external force, this pressure increase will be transmitted to all points of the static fluid in an instant.

The inside of the hydraulic jack is mainly a U-shaped structure where a small piston is connected to a large piston and similar to a communicating device. The hydraulic pressure of the large piston is increased by pressing the hand lever connected to the small piston to transfer the liquid to the large piston. At this time, some people may not understand. A few tons of power still depends on people using the same pressure to complete the lifting?
Of course not. If this is the case, then the design of this hydraulic jack is meaningless. It uses Pascal’s law in physics. The ratio of the contact area of ​​the large and small pistons to the liquid is equal to the pressure ratio. Assuming that the force on the hand is increased by 20 times by pressing the lever to the small piston, and the contact area ratio of the large and small pistons is 20:1, then the pressure from the small piston to the large piston will double to 20*20=400 times. We go to use the pressure of 30KG to press the hand lever, the force of the big piston will reach 30KG*400=12T.

Lower energy transfer, under the action of Pascal’s principle, there can be an instant qualitative flyover, so as to achieve the maximum energy conversion. This is why a small hydraulic jack contains such a huge amount of energy.

Post time: Nov-05-2021