Warmup:

1
Warm-up

• What causes something to sink in water?
• What causes something to float?
• How do you throw a curveball?

2
Physics Invention Project

• How are the projects coming?
• Decide on the format of your presentation
• PowerPoint, posterboard, etc.
• Make sure you and your partner know whos doing
  what on the project
• You must make either a 3-D model or a 3-D
  schematic (drawing) of the invention.
• Prepare for a 5-minute presentation

3
Fluids

• Take out a piece of scratch paper.
• Hold the paper at one end and let it hang down in
  front of your mouth. If you blow across the top,
  what will happen?
• Fold it hamburger. Pinch the crease and hold
  it like a tent in front of your mouth. What will
  happen if you blow?

4
Fluids

• These examples demonstrate the Bernoulli
  Effect
• In a moving fluid, an increase in velocity is
  accompanied by a decrease in pressure (and vice
  versa).
• Remember, a fluid can be a liquid (like water) or
  a gas (like air).

5
Fluids

• When one side of the paper has less pressure
  (because of the increased velocity of the air
  when you blow), the paper will move towards the
  low pressure area.
• This applies to all objects that move through
  fluids (including
  airplanes, baseballs, clouds, etc)

6
Fluids

• How do airplane wings work?

7
Fluids

• How do airplane wings work?

8
Fluids

• How do airplane wings work?

9
Fluids

• How do airplane wings work?

10
Fluids

• How do airplane wings work?

11
Fluids

• How do airplane wings work?

12
Fluids

• How do airplane wings work?

Less Pressure
More Pressure
13
Fluids

• How do airplane wings work?

Result Lift !!!
14
Fluids

• How do curveballs work?

15
Fluids

• How do curveballs work?

16
Fluids

• How do curveballs work?

Result Curve !!!
17
Fluids

• Next fluid topic
• Will it float or will it sink?

18
Fluids

• An objects density determines whether it will
  float or sink.
• Density tells how much stuff there is crammed
  into an amount of space.
• Technically, it is a measurement of mass per unit
  of volume
• density mass/volume

19
Fluids

• Simple rules for floating and sinking
• If an objects density is greater than the
  density of water, it will sink. If its less
  than water, it will float.
• If the densities are exactly the same, the object
  is said to be neutrally buoyant.

20
Fluids

• How can we make our bodies float and sink?
• We sink if our lungs are empty. We are normally
  more dense than water.
• To float, we take a deep breath. This adds to
  our volume, making us less dense than water.

21
Fluids

• Cartesian Diver Lab

22
Homework

• Finish the Cartesian Diver Lab
• Work on the Physics Invention Project
• Print the Solar System Distance Activity for next
  class