Theory of Flight 04 - Balloons 1

OPENING QUESTION: 

Let's change groups first.... add up the characters in your first and last names and write them down on scratch paper.

Now have a conversation with your group and sketch a model for how a hot air balloon floats above the Earth (try to get VERY physic-y)

 

LEARNING GOAL FOR TODAY: Work on balloons

WORK O' THE DAY:

The buoyant force is defined to be the difference between the weight of an object and the force exerted on that object by the fluid surrounding that object <whew!>

Consider a piece of driftwood floating in Puget Sound:

1) Diagram the forces acting on that piece of wood.

2) Now consider what happens when that wood gets waterlogged -- so much so that it starts to sink.

  • diagram that situation
  • now explain that situation

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Answer:

The force pushing down on the driftwood (it's mass times gravity) is more than the force pushing up on the wood (the mass of water displaced by the wood times the force of gravity)

Now work with your group to revamp, revise and otherwise edit your model...

 

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1) Take a few moments and come up with a rubric for this part of the unit. It should include elements of the following:

  • Design
  • Performance
  • Physics (think buoyancy!)
  • Reflection

Basic design:

1) Cut out top using stencil # 1

2) Use full tissue paper sheets to make sides

3) Cut out bottom form tissue paper using stencil #4 <notice how it narrows to more easily fit around the nozzle of our hot air dispensing device>

Advanced design:

1) Design your own balloon

2) Use full tissue paper sheets to make sides

3) Cut out bottom form tissue paper using stencil #4 <notice how it narrows to more easily fit around the nozzle of our hot air dispensing device>

 

  • Teamwork
  • Buoyancy
  • Design/Creativity
  • Balloon Performance
  • Reflection

WORDS O' THE DAY:

Buoyancy