1. Forces in Fluids

2. Section 1: Pressure
Section 2: Floating and Sinking
Section 3: Pascal’s Principle
Section 4: Applying Bernoulli’s Principle

3. Pressure

4. Pressure
Pressure - the force exerted on a surface divided by the area over which the force is exerted.

5. Pressure
Which type of shoe exerts more pressure on the surface?

6. Calculating Pressure

7. Fluid Pressure Fluid - substance that can easily flow.
All of the forces exerted by the individual molecules in a fluid add together to make up the pressure exerted by the fluid.

8. Atmospheric Pressure
Because air has mass, gravity acts on all of the air molecules in our atmosphere, creating tremendous pressure at sea level.
The pressure inside our bodies balances the pressure outside our bodies, so we don’t feel a thing!

9. Variations in Fluid Pressure
Air pressure decreases as elevation increases.
Water pressure increases as depth increases.

10. Fluid pressure precautions
Oxygen masks in cabin of airplane, necessary to breathe if the cabin becomes depressurized.
Newt suit - designed to hold up under intense pressures of the deep sea

11. Floating or Sinking
Why do some things in the ocean float but others sink?

12. Floating and Sinking: Archimedes’ Principle
Archimedes Principle virtual lab

13. Buoyancy Buoyant Force - force that water exerts on submerged objects
Acts against gravity and makes objects feel lighter

14. Controlling Buoyancy

15. Density

16. Density
The density of pure water is 1g/cm3
Pine
Oak
Cedar

17. Buoyancy: A Powerful Force!

18. Pascal’s Principle
Pascal’s Principle - When a force is applied to a confined fluid, the change in pressure is transmitted equally to all parts of the fluid.

19. Examples of Pascal’s Principle in Real World

20. More Examples of Pascal’s Principle in Real World

21. Hydraulic Systems
FORCE IS MULTIPLIED
LARGER AREA

22. Hydraulic Systems

23. Hydraulic Brakes

24. Bernoulli Predictions Lab

25. Bernoulli’s Principle
Bernoulli’s Principle - As the speed of a moving fluid increases, the pressure within the fluid decreases.
Faster fluid = less pressure

26. Bernoulli’s Principle at Work

27. Bernoulli’s Principle at Work

28. Bernoulli’s Principle at Work