U.06 Hydraulics

Day 01 - Introduction to Pascal's Principle

Thanks to Pascal, we know that pressure is equal to force divided by the area against which that force is applied, and that in a closed hydraulic system, we can then deduce that the pressure at one end of the system is equal to the pressure at the other end of the system. That means we can apply the following equation:

P = F1/A1 = F2/A2

Use algebra on the above equation to solve the problems on Worksheet 6A. That .pdf keeps getting corrupted for some reason, so I am also including all 6 questions here, below. I will demonstrate a similar problem on the board so you can see how to document the steps and solve the problem.

  1. The large piston in a hydraulic lift has an area of 250 cm2. What force must be applied to the small piston with an area of 25 cm2 in order to raise a car of mass 1500 kg?
  2. A trash compactor pushes down with a force of 500 N on a 3 cm2 input piston, causing a force of 30,000 N to crush the trash. What is the area of the output piston that crushes the trash?
  3. When the button of a trash compactor is pushed, a force of 350 N pushes down on a 1.3 cm2 input piston, creating a force of 22,076 N to crush the trash. What is the area of the piston that crushes the trash?
  4. Johnny the auto mechanic is raising a 1200 kg car on her hydraulic lift so that she can work underneath. If the area of the input piston is 12 cm2, while the output piston has an area of 700 cm2, what force must be exerted on the input piston to lift the car?
  5. Marc’s favorite ride at Busch Gardens is the Flying Umbrella, which is lifted by a hydraulic jack. The operator activates the ride by applying a force of 72N to a 30cm2 cylindrical piston, which holds the 20,000N ride off the ground. What is the area of the piston that holds the ride?
  6. Mr. Sharlow is raising a 2000kg car on his hydraulic lift. If the area of the input piston is 9cm2, while the area of the output piston is 630 cm2, what force must be exerted on the input piston to lift the car?

    7. hydraulics
    the branch of engineering concerned with the conveyance of liquids through pipes and channels, especially as a source of mechanical force or control.