Pascal’s Principle

Pascal's Principle

The Pascal's principle is as follows.

"Suppose a closed tube filled with uncompressed fluid. Then, the pressure of this tube's inside is the same everywhere."

For example, If you press any part of the tube that containing the toothpaste, the toothpaste will come out constantly. This is because the same pressure is applied to all parts of the tube.

Application of Pascal's Principle

Pascal's principle is used to generate large forces with little force.
Let's consider two cylinders with the same inner diameter area as shown in the figure below. When you push or pull one of the pistons, the other piston moves to the same length. In this case, only the direction of the force can be changed, and the magnitude of the force does not changed.

If the inner diameters of the two cylinders are different, the moving distance also differs. According to the "principle of work", a cylinder that moves a short distance can generate greater force. The product of force and moving distance is always constant.

'Hydraulic cylinders' are often used when large forces are needed throughout the industry. Automobile lifts, excavators, dump trucks that pick up the loader, and farm machineries are applications of hydraulic technology.