1. Pascal’s Principle

2. Transmitting Pressure
Watch Cartesian diver experiment….
Why did this occur?

3. Pascal’s Principle 1. Fluid exerts pressure on any surface it touches.
Example: water in a bottle
What happens if you squeeze a bottle with more force if the lid is on?

4. Pascal’s Principle
Pressure increases by the same amount throughout an enclosed or confined fluid.
When force is applied to a confined fluid, the change in pressure is transmitted equally to all parts of the fluid.

5. Piston Tube Experiment
A piston is like a stopper that slides up an down in a tube.
An increase in fluid pressure will be transmitted to the right piston.
Both pistons experience the same fluid pressure because they have the same surface area.

6. Piston Tube Experiment
The right piston has a greater surface area than the left piston. If the left piston is 1cm2 and the right is 9cm2 the amount of force on the right piston will be nine times greater, because pressure is transmitted equally.

7. Hydraulic System
Hydraulic systems use liquids to transmit pressure and multiply force in a confined fluid.
Examples:
Mechanics lift cars off of the ground.
Small brake pedal on a car to stop it.

8. 1. lift heavy ladder on a firetruck
Hydraulic Lifts
1. lift heavy ladder on a firetruck
2. dump trucks
3. backhoes
3. snowplows
4. Construction cranes

9. Hydraulic Brakes
1. When a driver pushes on a brake, he/she pushes on a small piston. 2. The piston exerts pressure on the brake fluidpushes on a larger piston. 3. Each large piston pushes a brake pad against the wheel to slow it using friction.

10. Hydraulic Brakes
Since the amount of force on the small piston affects the amount of force in the fluid to the large piston, a person can brake a little bit or a lot!