1. 11-3/11-4: Pascal’s & Bernoulli’s Principles
What is fluid pressure and how is it related to motion?

2. What will happen if you squeeze one side of the bag of water?
Anticipatory Set
What will happen if you squeeze one side of the bag of water?

3. California Standards
Science Standard 8.8.c: Students know the buoyant force on an object in a fluid is an upward force equal to the weight of the fluid the object has displaced.
Science Standard 8.2.e: Students know that when the forces on an object are unbalanced, the object will change its velocity.

4. Input
Pascal’s principle: pressure increases by the same amount throughout an enclosed or confined fluid.
hydraulic system: uses liquids to transmit pressure and multiple force in a confined fluid.
Bernoulli’s Principle: the faster a fluid moves, the less pressure the fluid exerts.
lift: an upward force.

5. Transmitting Pressure in a Fluid
Input & Modeling
Transmitting Pressure in a Fluid
When force is applied to a confined fluid, the change in pressure is transmitted equally to all parts of the fluid.

6. Input & Modeling Hydraulic Devices
In a hydraulic device, a force applied to one piston increases the fluid pressure equally throughout the fluid.

7. Input & Modeling Hydraulic Devices
By changing the size of the pistons, the force can be multiplied.

8. Comparing Hydraulic Lifts
Input & Modeling
Comparing Hydraulic Lifts
Reading Graphs:
For Lift A, how much force must be applied to lift a 12,000-N object?
3,000 N

9. Comparing Hydraulic Lifts
Input & Modeling
Comparing Hydraulic Lifts
Interpreting Data:
By how much is the applied force multiplied for Lift A? Lift B?
Lift A: multiplied by 4
Lift B: multiplied by 2

10. Comparing Hydraulic Lifts
Input and Modeling
Comparing Hydraulic Lifts
Interpreting Data:
What does the slope of each line represent?
The slopes gives the ratio of the lifting force to the applied force. The greater the slope, the more the lift multiplies force.

11. Comparing Hydraulic Lifts
Input and Modeling
Comparing Hydraulic Lifts
Drawing Conclusions:
Which lift would you choose if you wanted to lift a weight of 4,000 N?
Lift A, because it multiplies force more than lift B.

12. Input & Modeling Hydraulic Brakes
The hydraulic brake system of a car multiplies the force exerted on the brake pedal.

13. Bernoulli’s Principle
Input & Modeling
Bernoulli’s Principle
Bernoulli’s principle states that as the speed of a moving fluid increases, the pressure exerted by the fluid decreases.

14. Applying Bernoulli’s Principle
Input & Modeling
Applying Bernoulli’s Principle
Bernoulli’s principle helps explain how planes fly.

15. Applying Bernoulli’s Principle
Input & Modeling
Applying Bernoulli’s Principle
An atomizer is an application of Bernoulli’s principle.

16. Applying Bernoulli’s Principle
Input & Modeling
Applying Bernoulli’s Principle
Thanks in part to Bernoulli's principle, you can enjoy an evening by a warm fireplace without the room filling up with smoke.

17. Applying Bernoulli’s Principle
Input & Modeling
Applying Bernoulli’s Principle
Like an airplane wing, a flying disk uses a curved upper surface to create lift.

18. C4U
Quick Quiz PPT
Get out your whiteboard and marker!

19. HOMEWORK CONNECTION Read pages 432-441 in your Science textbook.
Complete the Section 11-3/11-4 Review & Reinforce
Write a detailed SUMMARY of the section and complete the UNANSWERED QUESTIONS section of your notes.
Choose two of the remaining Depth & Complexity ICONS in your notes and explain how they relate to this section.