Investigating Static Forces
in Nature:
The Mystery of the Gecko
Physical Science
Lesson 3
What Are Your Ideas About Small Sizes?
What Are Your Ideas About Small Sizes?
1
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Nanotechnology
Your Thoughts About Nanoscale Science and Technology
Definition
Information
Nanoscale Science
Examples
What Are Your Ideas About Small Sizes?
Non-Examples
2
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How small is a nanometer (and other small sizes)?
Start with a centimeter.
A centimeter is about the size of a bean.
1 cm
Now divide it into 10 equal parts.
1 mm
Now divide that into 10 equal
parts.
Each part is a millimeter long. About
the size of a flea.
Each part is 100 micrometers long.
About the size (width) of a human hair.
100 mm
Now divide that into 100 equal
parts.
Each part is a micrometer long. About
the size of a bacterium.
1 mm
Now divide that into 10 equal
parts.
Each part is a 100 nanometers long.
About the size of a virus.
100 nm
Finally divide that into 100 equal
parts.
Each part is a nanometer. About the
size of a small molecule.
1 nm
What Are Your Ideas About Small Sizes?
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What Is a Nanometer?
A nanometer is a unit of spatial measurement
that is 10-9 meter or one-billionth of a meter.
milli
micro
0.001
meter
10-3
0.000001
meter
10-6
Flea
1 mm
Bacterium
1 mm
nano
0.000000001
meter
10-9
Small
Molecule
1 nm
pico
0.000000000001
meter
10-12
Hydrogen Atom (74 pm)
74 pm
What Are Your Ideas About Small Sizes?
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What are Your Ideas about Small
Sizes?
• Name some objects that are smaller than a
penny.
• Identify which of those objects would be
considered microscopic (unable to be seen
with the unaided eye).
Image 3.1
What Are Your Ideas About Small Sizes?
Image 3.2
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Arrange These Objects From Largest
to Smallest
What Are Your Ideas About Small Sizes?
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Questions
a) Which of the image sort ranges was the easiest to rank?
Why?
b) Which range was the most difficult? Why?
c) Circle the largest in each of the following pairs:
Ant
Grain of Sand
Virus
White Blood Cell
Virus
DNA Molecule
Atom
DNA Molecule
d) How do nanoparticles, such as the carbon nanotube or
buckey ball, compare with cells in size?
e) How do nanoparticles compare with atoms in size?
What Are Your Ideas About Small Sizes?
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Making Connections
•
•
•
How has your thinking about small sizes
changed after completing the computer
activity?
Are the instruments that are used for each of
these size ranges the same? Explain.
What should we explore next?
What Are Your Ideas About Small Sizes?
8
© 2009 McREL
Nanotechnology: Life Changing?
“Nanoscience and technology will change the nature of almost
every human-made object in the 21st century.”
— M. C. Roco, R. S. Williams, & P. Alivisatos, 1999
“The government and funding agencies have recognized that the
societal and ethical implications of this new field must be
explored right alongside research in the lab.”
— Kristen Kulinowski, Executive Director
Rice University’s Center for Biological and
Environmental Nanotechnology
What Are Your Ideas About Small Sizes?
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© 2009 McREL
Time to Update!
Definition
Examples
What Are Your Ideas About Small Sizes?
Information
Nanoscale
Science
NonExamples
10
© 2009 McREL
Flow Chart
Chart
Flow
1. How Can a Gecko
Walk on a Ceiling?
Scale: Visible
Dominant Force:
Gravity
Tools: Eye
5. What Types of Forces
Can Hold Objects
Together?
2. What Do We Mean
When We Speak
About Surfaces in
Contact?
Scale: Visible
Force: Gravity
Tools: Eyes
6. How MUCH Force Is
Needed to Make an
Object Stick? What
Factors Affect the
STRENGTH of Force
Acting?
What Are Your Ideas About Small Sizes?
3.
What Are Your Ideas
of Small Sizes?
4. What Do We Learn
When We Look More
Closely?
Scale: Visible/
Invisible
Dominant Force:
Varies
Tools: Eyes,
Instruments
7. How Do We Measure
Forces at the Nano
Level?
8. How Can a Gecko
Walk on a Ceiling?
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