WEBVTT

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[Music] foreign

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With an understanding of aerodynamic forces,
learners will be ready to explore the balloon

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aerodynamics challenge. Teams will work through
the eight steps of the design process to build a

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prototype. For this balloon challenge, learners
will modify a helium-filled balloon to make

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it neutrally buoyant, either inside like a
classroom, or in a safe outdoor environment.

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For this engineering experiment, learners will
need the following materials: one helium balloon,

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beads, grains of rice, paper clips, or objects
of similar mass to weigh down the balloon.

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Paper cups, three yards of thin string, yarn
and optional materials include scissors,

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tape and a pencil for punching holes, as
well as a meter stick to measure distance.

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To begin the design process, teams will
first begin by exploring designs for

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the systems holding the mass underneath
the balloon. Draw as many ideas as you

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can to hold the cup upright and balance the
balloons payload to create neutral buoyancy.

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By now, learners should begin to model and
build their prototype with the helium balloon.

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They should be asking lots of questions during
this phase, such as how many beats should go

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into the paper cups, or how are they going
to tie the paper cups to their prototypes,

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and how are they going to put
all of these pieces together?

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Once you have a plan, it's time for testing
the model. Learners should evaluate their

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prototypes and see how the balloon holds up
during testing. Note any problems that occur.

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Does the balloon fall straight to the ground? To
counter this, learners will have to take out some

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of the beads or reconstruct their cup structures.
Does the balloon float away because there's not

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enough beads? Sometimes adding additional weight
or other objects will help balance your buoyancy.

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This process of prototyping is called refining
the design, working as a team to come up with new

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ideas and retest one's design. Ask others to share
their solutions and designs, verifying that their

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balloons are neutrally buoyant. What strategies
did they implore through the engineering design

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process? Learners of all ages are working
collaboratively to construct prototypes and

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learn about the aerodynamic forces that are vital
to understanding how objects move through the air.

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Thanks for watching

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[Music]