Practice 2 - Developing and Using Models

Summary

In this educational video, Paul Andersen explores the significance of models in science and engineering. He explains how models help explain phenomena, share understanding, analyze systems, and predict performance. The video delves into various types of models, including physical, conceptual, and computer simulations, and emphasizes the importance of developing these skills from an early age. Andersen suggests starting with simple drawings and progressing to more complex simulations and design testing, ultimately aiming to refine students' modeling abilities throughout their education.

Takeaways

• 🧠 Models are crucial in science for explaining phenomena and in engineering for analyzing and simulating system performance.
• 👀 The script uses an optical illusion to demonstrate how our mental models can be deceived, emphasizing the importance of external models for shared understanding.
• 🌐 A mental model is personal, unstable, and can be incomplete, unlike physical or conceptual models which are clear, shared, and act as analogs for phenomena or designs.
• 🌌 The script illustrates different types of models including structural, behavioral, and functional, with examples like DNA structure and magnetic field lines.
• 📊 Models can be manifested in various forms such as diagrams, computer simulations, analogies, and mathematical models, each serving a distinct purpose in understanding or testing concepts.
• 🔧 In engineering, models are used to test designs through methods like crash tests and to build designs using tools like CAD software and 3D printers.
• 📚 The goal of science education is to help students develop models, starting with simple drawings and progressing to more complex simulations and design tests.
• 🎯 The script suggests a progression for model development, from basic drawings in elementary school to using simulation software and participating in design competitions in high school.
• 🏫 Early introduction to model building through drawing and simple experiments can lay a strong foundation for students' scientific and engineering understanding.
• 💡 Netlogo is highlighted as a valuable simulation software for scientific modeling, allowing students to interact with and create their own models.
• 🏁 Design competitions, such as mousetrap cars, are recommended as a hands-on way for students to test their models, integrating science and engineering principles.

Q & A

What is the primary purpose of models in science and engineering?

In science, models are used to explain phenomena and share understanding of how the world works. In engineering, they are used to analyze systems, often through simulations or physical models to see how a design will perform.

What is the difference between a mental model and a physical or conceptual model?

Mental models are internal, individual, and can be unstable or incomplete. Physical or conceptual models, on the other hand, are external, shared by everyone, clear, and act as analogs for phenomena or designs.

How does the optical illusion with squares A and B illustrate the concept of mental models?

The optical illusion demonstrates how mental models can be deceived by external factors, like the shadow in the illusion, leading to incorrect assumptions about the darkness of squares A and B.

What is an example of a structural model mentioned in the script?

An example of a structural model is the model of the structure of DNA, which helps explain how it works despite being too small to be seen directly.

How can behavioral models be represented?

Behavioral models can be represented through simulations or physical demonstrations, such as observing ants foraging for food or testing a wing in a wind tunnel.

What is the role of diagrams in modeling as discussed in the script?

Diagrams serve as a type of model, such as Charles Darwin's branching diagram explaining speciation, which helps visualize and explain complex phenomena.

Why are computer simulations considered a type of model?

Computer simulations are considered models because they mimic real-world processes, like the simulation of osmosis, allowing for the study and understanding of phenomena in a controlled environment.

How do models assist in engineering design?

Models assist in engineering design by allowing for the testing of a design's performance through crash tests or simulations, and for the building of designs using tools like CAD software or 3D printers.

What is the goal of science education regarding the development and use of models?

The goal is to help students develop and use models by constructing drawings, representing phenomena, and using simulations and tests to refine their understanding and ability to explain and predict real-world events.

How can students be introduced to the concept of models in elementary education?

Students can be introduced to models by drawing pictures of objects, like insects, and their parts, or by constructing drawings after observing demonstrations, such as a car on a ramp.

What is the significance of competitions like mousetrap cars in model development?

Competitions like mousetrap cars are significant as they encourage students to build and test physical models, applying their understanding of science and engineering principles in a practical and creative way.

Outlines

00:00

🧠 Understanding Mental Models and Their Limitations

Paul Andersen introduces the concept of models in science and engineering, explaining their use in explaining phenomena and analyzing systems. He uses optical illusions to demonstrate how our mental models can be flawed, and contrasts these with physical, conceptual models that are clear, shared, and act as analogs. Andersen discusses different types of models, including structural, behavioral, and functional, and how they can be represented through diagrams, simulations, and mathematical models. The goal in science education is to help students develop these models, starting with simple drawings and progressing to more complex simulations and designs.

05:01

🎯 Developing and Refining Models in Education

The second paragraph focuses on the progression of model development in education. Andersen suggests starting with simple drawings in elementary school and gradually refining these models as students advance through middle and high school. He emphasizes the importance of early engagement with model building and the use of simulations for understanding complex phenomena. Software like Google Sketch-Up and Netlogo are mentioned as tools for building and interacting with models. Andersen also highlights the value of competitions, such as mousetrap car challenges, in testing and refining physical models. The paragraph concludes by reiterating the role of models as a shared, physical manifestation of mental models for explaining and testing phenomena.

Keywords

💡Mental Models

Mental models are personal, internal representations of how we perceive the world. In the video, Paul Andersen emphasizes how these models are individualized and used to solve problems or understand phenomena, but they can be unstable or incomplete. For example, he describes how people use mental models to interpret the optical illusion of two squares that appear to be different in darkness but are actually the same.

💡Physical Models

Physical models are external, shared representations of phenomena that are clear and stable. Unlike mental models, physical models can be used by others to analyze and predict behavior or performance. The video mentions various types of physical models, such as DNA structures and 3D printed parts, to demonstrate their utility in both science and engineering.

💡Conceptual Models

Conceptual models are theoretical representations used to explain how a system or phenomenon works. In the video, they are described as analogs that simplify complex systems, such as Darwin’s branching diagram of speciation. These models help visualize abstract concepts and share understanding among multiple people.

💡Simulations

Simulations are computer-based models that allow users to replicate and interact with complex systems or phenomena. In the video, Andersen discusses simulations as tools for exploring scientific concepts, such as the simulation of osmosis and ant foraging. These are valuable for testing and adjusting hypotheses in both science and engineering.

💡Engineering Models

Engineering models are tools used to test, design, and evaluate the performance of systems or products. In the video, Andersen highlights the use of models like crash tests and CAD (Computer-Aided Design) software to assess how well a design works before physical construction. They are crucial in optimizing design processes.

💡Behavioral Models

Behavioral models represent how a system or entity behaves under certain conditions. The video provides examples like ants foraging and wind tunnel testing, where these models help predict outcomes. Behavioral models are particularly useful in both science and engineering for analyzing dynamic systems.

💡Analogies

Analogies are comparisons between two different things that highlight their similarities, making complex concepts easier to understand. The video uses the analogy of fluid moving through a hose to explain how blood moves through vessels, illustrating how physical models can serve as analogs to real-world phenomena.

💡Scientific Modeling

Scientific modeling refers to the creation of models to explain and predict natural phenomena. The video explains that scientific models can take many forms, from diagrams to computer simulations, such as Darwin's diagram for speciation or a simulation of protein behavior. These models are essential for building scientific understanding.

💡Computer-Aided Design (CAD)

CAD refers to software used to create precise designs and models in engineering. In the video, Andersen explains how engineers use CAD to create digital models of products, such as motor parts, and test their functionality through simulations before physical production. CAD helps improve design accuracy and efficiency.

💡Netlogo

Netlogo is a software tool for creating and running agent-based simulations, allowing users to simulate and explore complex phenomena. In the video, Andersen highlights how students can use Netlogo to interact with scientific models, such as simulations of wolves and sheep populations, making it an effective educational tool for exploring systems.

Highlights

Models are crucial in science for explaining phenomena and in engineering for analyzing systems.

A mental model is an internal, individual understanding that can be unstable and incomplete.

Physical, conceptual models are clear, shared, and act as analogs for phenomena or designs.

Structural models, like DNA, help explain the structure of unseen entities.

Behavioral models, such as ant foraging or fluid dynamics, predict performance.

Functional models, like magnetic field lines, represent the functions of a system.

Diagrams, like Darwin's branching diagram, are a form of model used to explain concepts.

Computer simulations, such as protein folding, are advanced models used in scientific research.

Analogy models, like fluid flow in a hose, help explain complex processes.

Mathematical models, like the ideal gas law, use formulas to describe scientific principles.

Simulations, such as osmosis models, visually demonstrate scientific processes.

In engineering, models are used to test designs, like crash tests, to ensure performance.

CAD software and 3D printing allow for the physical creation of models for testing.

The goal in science education is to help students develop and use models effectively.

Elementary students can start model building with simple drawings and representations.

Middle and high school students can refine models and represent actual phenomena.

Simulation software like Netlogo allows students to interact with and create models.

Competitions, such as mousetrap cars, encourage students to test and refine their designs.

Models are a physical manifestation of mental models, shared for explaining and testing phenomena.

Transcripts

Hi. It's Paul Andersen and this is Science and Engineering Practice 2, Developing

and Using Models. Models are important in science and engineering for a couple of different

ways. In science we use models and modeling to explain phenomena. Or to share an understanding

of how the world works. In engineering we us it to analyze systems. And lots of times

we'll do simulations or build models to see how a design is going to perform. And so before

we get to models though, I really want you to understand what a model is. And so I am

going to start with a couple of questions. So first of all in the drawing right here,

which square do you think is darker? A or B? Pause the video if you want to take a look

for a second. And of course it's a trick question. They both are going to be the same level of

darkness. We could even reconstruct this. So if we take those two squares, A and B,

and rebuild the optical illusion, watch carefully, all of a sudden B gets lighter. And so we're

tricked by the shadow of this cylinder. And so that would be a mental model you're using

to figure out which of those is darker. Let me one up with another question. So this is

a diagram of the earth and the moon. The scale is okay but they would be way farther apart.

You can see that one half of them is lit and then I've put the North Pole on the earth

so you can know where that is. So if you were standing here. If you were to stand right

here on the earth in the northern hemisphere, what would the moon look like, as seen from

the earth? So if you want to take a little bit of time you could pause the video. And

the right answer is D. If you missed that one, then your mental model might not be working.

Your mental model of the way the earth and the moon and the phases of the moon work might

be ineffective. And so to solve problems to understand the world, we use mental models.

And they're great. That's the way that you work. The problem with mental models is that

they're just yours. They're yours alone. They're inside your brain. They're unstable. They're

idiosyncratic, that means that they're going to be different in every individual and also

they're lots of times incomplete or ineffective. And so the mental model is not what we're

talking about when we're talking about modeling. What we're talking about are physical, conceptual

models. And so those are clear. They're shared by every one. They're external and they act

as an analog. In other words they're an analogy for how phenomena work or how designs work.

And so those analogs can basically be structural. This is would be the structure of DNA in a

model. We don't really, we haven't seen DNA per se. We can't see it. It's too small. But

we can building models that explain how it works. It could be behavioral model. How it's

going to perform. So this right here is going to be ants foraging or we could look at a

wing in a wind tunnel. That could be a behavioral model. Or we could look at it's functions.

These are going to be the lines of magnetism around the different fields of a magnet. And

so these are different analogs. And then we can manifest those analogs in a number of

different ways. And so you could make a model that's just simply a diagram. This was a diagram

created by Charles Darwin when he was trying to explain how speciation occurs. And he draws

this branching diagram from a common ancestor. Or this could be a computer simulation of

a protein. This is myoglobin. We could use an analogy as a model. For example, if I understand

how fluid moves through a hose I could use that to explain how blood is going to move

through the vessels or I could use just a mathematical model. So this could be the ideal

gas law. It's simply a formula that explains what happens as we increase pressure or decrease

volume or increase temperature. We can understand what's happening. Or even a simulation. This

is a simulation of osmosis as water moves through a semi-permeable membrane. The computer

simulation. These are all different types of models. In engineering we use models, lots

of times to test a design. So this crash test, and the crash test dummies and all of the

material we're getting back from that is allowing us to see how well a design works. We can

also use models to build designs. And so we can use computer aided design software, CAD

software to build material. We can physically build it now. So this would be a three-dimensional

printer. A 3-D printer where we can print materials. We could actually print like this

part of a motor and then we can see how that performs. And so again models are going to

by physical, shared, clear understandings. And they're really the manifestation of mental models.

And so the goal in science education is help students to develop models. And they do that

first of all by constructing drawings and then representing phenomena. And then finally

we're going to use those models. We can use models through simulations. And then we can

also test designs. And so let me talk about a nice progression for this. In other words

going back to the analogy of throwing darts at a dart board. We want our students from

the time they begin education to start developing and using models. And we want to refine those

through the years and get better and better and close and closer to the bulls eye. So

when there seniors in high school they really are good at using models. And so what would

be a good way to start this in the elementary. Well you could show them a picture of an insect

and have them draw an insect and then draw the parts the insect. Or you could give them

a demonstration and then have them draw parts of it. So for example a car on a ramp before

studying how fast material moves down a ramp, make sure you get students right away constructing

drawings. You know drawing water and how it warms up during the day and how light effects

plants. And so the more drawing we can do earlier, the more model building we can do

earlier the better. As we get older we can start to refine those models. And so we can

represent actual phenomena. And so now as we get into middle school and on to high school

we could label forces acting on that same drawing. And so this would be a force diagram.

As we move on we also want to start using simulations. And there's a number of different

simulation softwares out there that you can use to build models, like Google Sketch-Up

is an example of one where you can build designs. But if you want to do scientific modeling

a great choice would be Netlogo. You can download it for Mac & Windows. And basically they have

a number of different simulations. So you can simulate phenomena and then you can kid

of interact with that. And so this one right here is a Netlogo simulation where you're

looking at wolves and sheep. And then the food for the sheep and how they'll move over

time. This one is a video I created of ants. And so basically what you have are ants that

are foraging on food and then when they pick up food they're going to bring that food back

to the nest which is in the middle. But they're going to drop off chemicals as they move back

and that's going to diffuse out. And so again this is simply a computer model that shows

how ants feed but then students can interact with a lot of the inputs and so they can play

around with it and they can see how that model is used. And they can also create models themselves

if you know any kind of programing. You can produce these really powerful models in Netlogo.

And then finally, we can test designs. And so the best way to really figure out the importance

of testing designs is to actually do competitions. And so mousetrap cars is something that I've

done before. Basically you're creating a car that can move just through the power of a

mouse trap. And when you give students a question or a problem like how can you do that and

competition, they're going to come up with ideas that are simply amazing. And so not

only are they building models, they're building physical models that they can test. And so

they're really doing engineering. They're doing science. They're putting it all together.

And so what are models again? They're really a physical manifestation of this mental model

that we can all share and we can use that to explain phenomena and also test designs.

And I hope that was helpful.