Instructional impact on high school physics students’ nanoscience conceptions

Directions

For each situation below in questions numbered 1–8, please read the statements that give possible answers [labeled (a), (b), (c)]. PLEASE ANSWER EACH PART (a), (b), (c) – THESE ARE NOT MULTIPLE CHOICE WHERE ONLY ONE IS CHOSEN.

On the scale below each answer, indicate your degree of agreement or disagreement with the answer given by circling the number that best represents your choice. Use the middle numbers to indicate your level of uncertainty about the answer given when appropriate.

1. A Japanese company has built a tiny car that is about 8 mm long – the size of a grain of rice. It has 24 parts, including tires, wheels, axles, and a motor. If another company were to make a claim (but have not yet shown anyone) that they built a similar working car with 24 parts that was only 8 nm long – 1 million times smaller than the grain of rice size – how believable would their claim be?

(1a) Not at all believable because that size is too small for anything to serve as the building blocks.

(1b) Very believable because scientists are learning how to make things smaller and smaller, and they would likely be able to make a car that size very soon.

(1c) Somewhat believable because there is no limit on how small a car can be built, but such a tiny size is not likely to be possible so soon.

2. Suppose a paintbrush of a certain width was used to paint a wall. Assuming that the person using the brush makes the same number of paint strokes per minute, how would the time needed to paint a new wall be changed if the new wall was 10 times as long and high as the original wall and the brush used was 10 times as wide as the original brush?

(2a) The time would be about the same because they are both 10 times bigger.

(2b) The time would be significantly shorter because a wider brush is much more efficient at covering wall space with paint.

(2c) The time would be significantly longer because the wall space to paint with the wider brush increased more than the brush’s working edge.

3. If a deer and all its parts were to become 10 times its normal height, length, and thickness, how would such a change affect the leg strength of this gigantic deer compared with a normal-sized deer?

(3a) The gigantic deer’s legs become bigger and stronger and so they would carry that gigantic deer more easily than the normal deer’s legs would carry the normal deer.

(3b) The gigantic deer’s body weight would increase more than the leg strength and so the legs of the gigantic deer would not easily support such a huge body.

(3c) As both the body and the legs increase in size, the gigantic deer’s legs would support it about equally well as the normal deer’s legs would support the normal deer.

4. Human cells, many of which are approximately spherical in shape, take in nutrients and oxygen through the surface area of their cell membranes. These nutrients and oxygen must then spread themselves throughout the volume of the interior of the cell in order for the cell to function well. How might this process be different if a cell’s diameter were 50 times the typical cell diameter?

(4a) Because the interior volume of the bigger cell increased more than the membrane’s surface area did, it would be more difficult for the larger cell to get enough nutrients and oxygen everywhere inside.

(4b) Because both the surface area of the cell membrane and the interior volume of the cell increased 50 times, the nutrients and oxygen would get into the interior volume of the cell about equally well as it would for the normal-sized cell.

(4c) Because the surface area of the bigger cell increased more than the interior volume did, it would be easier for the larger cell to get enough nutrients and oxygen everywhere inside.

5. Scientists who work in the field of nanoscience and nanotechnology sometimes speak about mentally “jumping to the nanoscale world” when describing how they think about their work. Why might it be helpful to structure one’s thinking about nanoscience in this way?

(5a) Characteristics and features of the nanoscale world have been well defined by previous scientists, and mentally transitioning to that nanoscale world reminds and refreshes knowledge of them. In order for current scientists to describe their work to others and to help advance the state of knowledge related to nanoscience, they must be able to connect their work to those characteristics and features that the larger scientific community already agrees as useful for this purpose.

(5b) Because the science that happens at the nanoscale world is so unpredictable, scientists must be able to concentrate on their experiments in order to understand the outcomes. Mentally transitioning to a different world helps to generate the necessary concentration in order to productively understand their work.

(5c) The ways in which materials interact, along with the properties and behaviors found to exist at the nanometer scale, are often very different from our everyday experiences at normal human scale, and often different from those at other scales as well. It is helpful to put aside our existing assumptions and expectations by mentally transitioning to a different world with its own rules in order to best make sense of what is happening there.

6. Nanotechnology is a field of science that has been getting more and more exposure and attention in the media in recent years. Why is it now (the past few years), rather than 40 or 50 years ago or even earlier, that this particular field of science is such a relatively hot topic that seems to be of interest to more and more people?

(6a) Before the last few years, scientists were not aware of the importance or potential of phenomena at the nanometer scale and did not consider that to be a fruitful area for investigation. Recent accidental discoveries revealed the promise of nanotechnology, which led to the current increased interest in explorations.

(6b) In the past (e.g., 40–50 years ago), the US government and other influential sources decided not to fund projects exploring nanotechnology because of budget limitations. However, with the technology boom of the 1990s into the early 2000s, there was additional money available, especially for technology-related research, and the US government decided that the time was right for nanotechnology to become a more significant field of scientific exploration.

(6c) Different scientific tools are needed to work with material at the nanometer scale because tools such as the light microscope do not provide enough resolution for nanoscale phenomena. It is only in the last few years that a wide range of tools have been developed that allow scientists to manipulate and image at the nanoscale, and thus it is only recently that scientific exploration of nanotechnology phenomena has become possible.

7. Since the development of various types of microscopes during the past 400 years, many areas of scientific exploration have involved investigations of objects and phenomena that are too small to be seen with the unaided eye. This has proven very beneficial in many ways, for example in determining how various germs cause diseases or how molecules react and combine to form new substances in predictable ways. When thinking about the sizes and scale of the various microscopic phenomena that are now a common part of science, scientists generally agree that

(7a) Compared with microscopic phenomena, which all work with similarly small objects, large-scale scientific investigations such as those that look at globe-spanning issues like continental drift require more attention to the scale of the phenomena. Because visible phenomena (e.g., from an ant to the earth) span a larger range of size differences than do microscopic phenomena, the scale of the topic is of more significance for investigations into visible phenomena than it is for microscopic phenomena.

(7b) Microscopic sizes span a large range of sizes, and the size range within which the investigations happen are an important part of designing the investigation. As invisibly small objects and phenomena vary greatly in size relative to one another, scientific investigations must take into account the scale of the phenomenon when designing the investigations.

(7c) Thinking and working with microscopic phenomena is complicated and difficult because we have to use special instruments to see them. However, as microscopic phenomena are all invisibly small, once a person has developed the ability to work with one aspect of this science (e.g., cellular biology), then (s)he can transfer that ability to other projects in the microscopic realm as they all work with similarly small objects.

8. One of the reasons scientists are excited about the potential for nanotechnology is because of the new relationships and interactions being discovered during nanotechnology investigations. These interactions offer the promise of utilizing novel materials that have properties different from what was available previously. Many of these potentially interesting results are due to the scale of the phenomena being explored. Why is the scale of the phenomena an important aspect of these interesting results?

(8a) At the nanometer scale, different forces dominate and different properties emerge that are not present in the same material at larger scale. These properties and behavior are not just trivially predictable from what we know about either small atoms or molecules, or about bulk matter, but rather represent a realm unique from either atomic scale or bulk scale.

(8b) As the behavior of bulk amounts of most materials are already well known, scientists have a strong knowledge base for predicting the behavior of smaller, nanometer-scale amounts of material. The nanometer scale permits the introduction of many more different types of materials into one small space, allowing the already-known bulk properties to be combined in predictable, unique, and interesting ways as part of the miniaturization processes now under way.

(8c) Because of the nanometer scale, large-scale processes that are well understood and have been used for a long time (e.g., how to build skyscrapers, ships, bridges; or how to create strong knots) can now be miniaturized and replicated in different applications. Because of the miniaturized scale, existing knowledge can be applied to unique situations such as designing mechanical structures to be incorporated into a person’s bloodstream, or embedding strength-enhancing knots within the fibers of clothes.