1. What Are Your Ideas About Small Sizes?1 © 2009 McREL Physical Science Lesson 3 What Are Your Ideas About Small Sizes? Investigating Static Forces in Nature: The Mystery of the Gecko

2. What Are Your Ideas About Small Sizes?2 © 2009 McREL Nanotechnology Your Thoughts About Nanoscale Science and Technology DefinitionInformation ExamplesNon-Examples Nanoscale Science

3. What Are Your Ideas About Small Sizes?3 © 2009 McREL Start with a centimeter. Now divide it into 10 equal parts. Now divide that into 10 equal parts. Now divide that into 100 equal parts. Now divide that into 10 equal parts. Finally divide that into 100 equal parts. A centimeter is about the size of a bean. 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. Each part is a micrometer long. About the size of a bacterium. Each part is a 100 nanometers long. About the size of a virus. Each part is a nanometer. About the size of a small molecule. How small is a nanometer (and other small sizes)? 1 cm 1 mm 100  m 1  m 100 nm 1 nm

4. What Are Your Ideas About Small Sizes?4 © 2009 McREL What Is a Nanometer? A nanometer is a unit of spatial measurement that is 10 -9 meter or one-billionth of a meter. 1 mm milli 0.001 meter 10 -3 Flea micro 0.000001 meter 10 -6 Bacterium nano 0.000000001 meter 10 -9 Small Molecule pico 0.000000000001 meter 10 -12 Hydrogen Atom (74 pm) 1  m 1 nm 74 pm

5. What Are Your Ideas About Small Sizes?5 © 2009 McREL 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 3.1Image 3.2

6. What Are Your Ideas About Small Sizes?6 © 2009 McREL Arrange These Objects From Largest to Smallest

7. What Are Your Ideas About Small Sizes?7 © 2009 McREL 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: AntGrain of Sand VirusWhite Blood Cell VirusDNA Molecule AtomDNA 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?

8. What Are Your Ideas About Small Sizes?8 © 2009 McREL 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?

9. What Are Your Ideas About Small Sizes?9 © 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

10. What Are Your Ideas About Small Sizes?10 © 2009 McREL Time to Update! Definition Non- Examples Examples Information Nanoscale Science

11. What Are Your Ideas About Small Sizes?11 © 2009 McREL Flow Chart 2. What Do We Mean When We Speak About Surfaces in Contact? Scale: Visible Force: Gravity Tools: Eyes 3.What Are Your Ideas of Small Sizes? Scale: Visible/ Invisible Dominant Force: Varies Tools: Eyes, Instruments 1. How Can a Gecko Walk on a Ceiling? Scale: Visible Dominant Force: Gravity Tools: Eye 4.What Do We Learn When We Look More Closely? 7. How Do We Measure Forces at the Nano Level? 5. What Types of Forces Can Hold Objects Together? 8. How Can a Gecko Walk on a Ceiling? 6. How MUCH Force Is Needed to Make an Object Stick? What Factors Affect the STRENGTH of Force Acting?