How Small is a Nanometer?
Summary
There are 1 billion (1,000,000,000) nanometers in a meter. In this classroom activity students will use dimensional analysis to gain an understanding of what that statement means.
CollapseLearning Goals
Students will develop a model for the relative size of a nanounit to its base unit. Students will use what they know about the metric system and apply their use of dimensional analysis to solve the problem and gain a sense of scale. Only typical classroom vocabulary is necessary with the possible exception of the prefix nano-. Nano- as a prefix means one millionth.
Context for Use
This classroom activity is appropriate for any high school math or science course. Students will need a working knowledge of dimensional analysis (factor-label method), scientific notation and calculator use. The activity should be completed in about 30 minutes and is appropriate during any introductory science unit that talks about the metric system.
Description and Teaching Materials
The day before you plan to do this activity, ask your students to bring in an object. Anything will work, a football, an index card, a cookie or a piece of candy. Place any limits on the object that you desire. To do the activity students will need a ruler, calculator and access to reference materials.
One way to introduce this activity is by asking the students what they know about nanotechnology. Some students will know nothing, some will be well informed. Most students will probably know that nano means something small, but may not know how small.
Tell the students that there are 1 billion (1,000,000,000) nanometers in a meter. Each of them brought in an object. Tell them that the object they brought in is to represent 1 nanometer and you'd like to know where the millionth one is located.
It doesn't matter if students use the metric system or not to do the calculations. If you have a preference make sure your students know. Students may have to make several unit conversions depending on what units are used and what units they find in their research.
Once students figure out "how big" one million of their objects really is they will probably need help figuring out where exactly that will be. You might prompt them with questions like would the millionth object still be in your town? your state? on Earth?
You could wind up this activity by discussing the applications of nanotechnology students see in their daily lives and career options available to them.
One way to introduce this activity is by asking the students what they know about nanotechnology. Some students will know nothing, some will be well informed. Most students will probably know that nano means something small, but may not know how small.
Tell the students that there are 1 billion (1,000,000,000) nanometers in a meter. Each of them brought in an object. Tell them that the object they brought in is to represent 1 nanometer and you'd like to know where the millionth one is located.
It doesn't matter if students use the metric system or not to do the calculations. If you have a preference make sure your students know. Students may have to make several unit conversions depending on what units are used and what units they find in their research.
Once students figure out "how big" one million of their objects really is they will probably need help figuring out where exactly that will be. You might prompt them with questions like would the millionth object still be in your town? your state? on Earth?
You could wind up this activity by discussing the applications of nanotechnology students see in their daily lives and career options available to them.
Teaching Notes and Tips
Be prepared with extra objects for students that forgot or pair them up. Some students will need help setting up the math and/or figuring out where that millionth object will be.
A web search will give you more than enough background and application knowledge about nanotechnology. One nice website is: http://mrsec.wisc.edu. This site includes some very nice lesson plans and activities that can be used to expand on this activity. This site reminds us that other units can use the prefix nano-, for example the blink of an eye takes about 1 nanoyear (one-billionth of a year). That means a blink of the eye is to a year as a nanometer is to a meter.
A good book is Nanoscale Science by M. Gail Jones, Michael R. Falvo, Amy R. Taylor, and Bethany P. Broadwell. A search for this book should result in some sample pages that include good information and experiments that will also supplement this activity. Depending on what direction you take in summing up this activity additional standards could be covered.
Example calculations: An index card measures 3" x 5", so 1 billion of them laid end to end would measure 5 billion inches. Converted to miles equals 78914 miles. (5,000,000,000 x 1'/12" x 1mile/5280' = 78914miles) The Earth's circumference is 24901 miles. That means the index cards laid end to end would go around the Earth a little more than three times! There are a lot of little units - nanounits - in one base unit.
A web search will give you more than enough background and application knowledge about nanotechnology. One nice website is: http://mrsec.wisc.edu. This site includes some very nice lesson plans and activities that can be used to expand on this activity. This site reminds us that other units can use the prefix nano-, for example the blink of an eye takes about 1 nanoyear (one-billionth of a year). That means a blink of the eye is to a year as a nanometer is to a meter.
A good book is Nanoscale Science by M. Gail Jones, Michael R. Falvo, Amy R. Taylor, and Bethany P. Broadwell. A search for this book should result in some sample pages that include good information and experiments that will also supplement this activity. Depending on what direction you take in summing up this activity additional standards could be covered.
Example calculations: An index card measures 3" x 5", so 1 billion of them laid end to end would measure 5 billion inches. Converted to miles equals 78914 miles. (5,000,000,000 x 1'/12" x 1mile/5280' = 78914miles) The Earth's circumference is 24901 miles. That means the index cards laid end to end would go around the Earth a little more than three times! There are a lot of little units - nanounits - in one base unit.
Assessment
Assessment of your students could be formal or informal. Informal assessment should include questions of "Does your answer make sense?" "Check with your neighbor, does your answer make sense when compared to theirs?" "If I say to you "A marble is to the Earth as a nanometer is to a meter" does that make sense to you? Substitute moon for marble with some groups and ask them to explain. Student calculations may be enough to tell you they have begun to understand the size of a nanounit. Should you wish to have a more formal assessment of their ability to do this exact kind of calculation you could always have them do similar calculations on a chapter test.
Standards
9.1.3.4.1 advances create a demand for new scientific knowledge, improved mathematics and new technologies
9.1.3.4.5 consistency and dimensional analysis can guide calculations and verification of results
9.1.1.1.7 innovations can challenge portions of accepted theories and models - with post activity discussion - at the nano scale our current models may not hold true
9.1.3.4.5 consistency and dimensional analysis can guide calculations and verification of results
9.1.1.1.7 innovations can challenge portions of accepted theories and models - with post activity discussion - at the nano scale our current models may not hold true