From Macro to Nano: Scaling and Units

Team members:Jenny DouglasGloria OportoAradhya Kumar

FacilitatorMike Hanna

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Target Audience

• Students in any introductory science course or lab

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From Macro to Nano: Scaling and Units

Students will be able to:• Communicate clearly with consistent units

that are appropriate to the context.• Apply order of magnitude and unit conversion

to accurately solve problems and compare results with scientific peers.

• Understand conversion of units and explain the consequences of incompatible units.

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$125 Million dollar questionHow could you lose $125M in one minute?

1. You put $125M on “red” on the roulette wheel in Los Vegas.

2. You lose the vacuum in the large hadron collider in Geneva.

3. You discover the human genome DNA sequence was heavily contaminated.

4. You lose a Mars Orbiter en route to the planet.

5. You lose all the primates in the NIH primary facility when PETA breaks in.

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• Mars Orbiter VideoMars Climate Orbiter - YouTube

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Intended orbit: 150 km altitude

Speed 1

Speed 2

Team 1:Design the software

Units: English (lb, in, ft)

Team 2:Provide the information

Units: Metric (SI) (km, m, g)

Newton(SI unit)

pound-force(English unit)

1 N ≡ 1 kg·m/s² ≈ 0.22481 lbF

1 lbF ≈ 4.448222 N ≡ gn·(1 lb)

Units of force

Example of units and its conversion

* The value of gn as used in the official definition of the kilogram-force is used here for all gravitational units.

 

 

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Activity

We are going at 60 miles/h, what would be the equivalent in m/s?

• What do you know?

• What do you need to know?

• Solve the problem

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Activity – follow upScaling - Surface area determination

Group 1: a=5 cm, b=1 cm

Group 2: a=2 in, b=0.4 in

a

b

b

Determine the surface area of shapes X and Y

X Y

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Activity – follow upPhysics – Unit conversion

Determine the acceleration due to gravity given the length in cm.

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