How a hydraulic jack works (3D Animation | Pascal Principle)

Summary

This video explains how a hydraulic jack uses Pascal's principle to lift heavy objects like a car. When a small force is applied to a piston in a fluid-filled system, it creates a pressure change that is transmitted equally throughout the fluid. This pressure pushes a larger piston upward with significantly more force. The key to lifting the car lies in the difference in piston sizes, where a large piston exerts 100 times the force of the smaller one. The video highlights how this mechanism adheres to the law of conservation of energy, despite the differing displacements of the pistons.

Takeaways

• 😀 A jack allows us to lift heavy objects like a car by turning a small force into a much larger force.
• 😀 The principle behind this process is Pascal's Principle, which was discovered by Blaise Pascal.
• 😀 According to Pascal's Principle, a pressure change in an incompressible fluid is transmitted throughout the fluid without any loss.
• 😀 When force is applied to the first piston, it creates a pressure change in the fluid, which is transmitted to the second piston.
• 😀 The pressure exerted on the second piston causes it to move upward, lifting the heavy object.
• 😀 Pascal's Principle ensures that the pressure is equal under both pistons, but the force exerted on the second piston can be different.
• 😀 Changing the base area of the pistons allows us to alter the force exerted on the second piston.
• 😀 If the first piston has a smaller radius than the second, the force exerted on the second piston will be greater by a factor corresponding to the area difference.
• 😀 For example, if the first piston has a radius of 10 cm and the second has a radius of 100 cm, the force on the second piston will be 100 times greater.
• 😀 The law of conservation of energy is not violated, as the displacement of the pistons is not the same (the first piston moves further than the second).
• 😀 The hydraulic jack works effectively due to the valves that control fluid flow in one direction, transforming the applied small force into a large lifting force.

Q & A

What is Pascal's Principle?

Pascal's Principle states that in an enclosed system filled with an incompressible fluid, any change in pressure is transmitted evenly throughout the fluid without any loss.

How does a hydraulic jack work?

A hydraulic jack works by using a small force applied to a piston in a fluid system, which is then transmitted to a larger piston, creating a much larger force that can lift heavy objects like a car.

What role does the fluid play in a hydraulic system?

The fluid in a hydraulic system transmits the pressure change evenly throughout the system, allowing the force applied to one piston to move the second piston and generate a greater force.

Why can a small force lift a heavy object using a hydraulic jack?

A small force can lift a heavy object because the hydraulic system amplifies the force based on the difference in the surface areas of the pistons, with the larger piston receiving a greater force.

What is the relationship between the piston sizes and the force exerted in a hydraulic system?

The force exerted on the second piston depends on the ratio of the areas of the pistons. If the second piston has a larger area, the force exerted on it will be much greater, based on Pascal's Principle.

How does the displacement of the pistons differ in a hydraulic system?

In a hydraulic system, the displacement of the pistons is inversely proportional to their sizes. When the small piston moves a large distance, the larger piston moves a much smaller distance.

What is the significance of the valve in a hydraulic jack?

The valve in a hydraulic jack ensures that the fluid flows in only one direction, allowing the force applied to the small piston to be transmitted to the larger piston, thereby lifting the load.

How is the law of conservation of energy maintained in a hydraulic jack?

The law of conservation of energy is maintained because, although the force is amplified, the displacement of the larger piston is much smaller than the displacement of the smaller piston, ensuring that energy is not lost.

Can Pascal's Principle be applied in systems other than hydraulic jacks?

Yes, Pascal's Principle can be applied in various systems, such as hydraulic brakes, lifts, and presses, wherever an incompressible fluid is used to transmit pressure.

What happens if the radius of the pistons in a hydraulic system is the same?

If the radius of both pistons is the same, the force applied to the first piston would be equally distributed to the second piston, but no amplification of force would occur.