Rocketry and Resistance

Noticing the effects of air resistance is easy.  Predicting the effects of air resistance on the motion of an object, however, is mathematically complex and beyond the scope of high school.  In Physics 11, students are introduced to motion without the effects of an atmosphere to keep it simple but highly unrealistic (especially for really fast things like bullets or rockets).  After years, my question is why even bother?  The students effectively learn that physics is only true in books and exams which only solidifies the separation between their informal and formal learning. Empirical tools can do an excellent job of modelling real motion of particles in an atmosphere while also introducing authentic challenges in science, which is more compelling for students (CTGV, 1992a).  The partial sacrifice is the simple analytical math part of the model.

The diagram below summarizes a T-GEM approach to a Compressed Air Rocketry project in which students are given the challenge of designing a rocket that will fly as far as possible on a short blast of air.

The project incorporates the affordances of social learning and making learning visible (Linn, 2003).  Students work iteratively in teams, making their learning visible through diagrams, group meetings, and presentations.  Three e-learning resources are needed for this:

1)  a camera with 60 fps or higher (most phones and all iPads)
2)  access to PhET Projectile Motion online simulator  https://phet.colorado.edu/sims/projectile-motion/projectile-motion_en.html
3)  Access to the freeware program Physics Tracker http://physlets.org/tracker/

Special attention should be paid to helping the students collect quality data, where scaffolding is necessary, or the evaluation part of the activity will collapse. Rich scientific data collection is not a teenage instinct!  On that note, Khan’s study references “experienced science teachers” so often that I am left wondering–is it implied that T-GEM as a framework is difficult to wield without appropriate experience or deep grounding in TPACK?

Cognition and Technology Group at Vanderbilt (1992a). The Jasper experiment: An exploration of issues in learning and instructional design. Educational Technology, Research and Development, 40(1), 65-80

Khan, S. (2007). Model-based inquiries in chemistry. Science Education, 91(6), 877-905.

Khan, S. (2010). New pedagogies for teaching with computer simulations. Journal of Science Education and Technology, 20(3), 215-232.

Linn, M., Clark, D., & Slotta, J. (2003). Wise design for knowledge integration. Science Education, 87(4), 517-538.

7 comments

  1. I’ve played around slightly with Tracker, though I wonder if you’ve encountered limitations on school computers being blocked from installing other programs than admin defaults: Like being able to update Java to run PhET simulations or having minimal storage capacities. Is the only solution having learners bring their own devices, as you mention with phones and iPads?

    Andrew

    1. Hello Andrew. Both PhET and Tracker have compatibility issues in my district. Although I understand that running a robust network of thousands of computers will have limitations, the level of dysfunction has driven our program to BYOD and developing our own “rogue” set of laptops that have relaxed networking limitations. This makes IT a bit nervous, but they are interested in the results so they go along with it. Similar issues arise with wifi connectivity and raspberry pi.

  2. Hi Michael

    I like the fact that you brought up that we are getting our students ready for the real world and we do not actually do real world problems (no air resistance).

    I wonder if a student benefit from 1) a science classroom with a lot of hands-on labs/activities and did not dive deeply into the concepts and ideas. OR 2) a classroom with a handful of labs/activities throughout the year and dive deeply into the concepts — just like the activity you proposed (Compressed Air Rocketry project).

    A good next step might be to share a teaching formula for teaching labs/activities.

    Christopher

    1. Hi Christopher,

      Thanks for you comment. This “depth or breadth” issue rages on and seems to be divided along “traditional” vs. “constructivist” lines. I had this Twitter exchange last week:

      ‘Tom Bennett‏ @tombennett71 Jul 2
      ‘The more student orientation you have, the lower the maths performance’. @greg_ashman at #ace2017

      Replying to @tombennett71 @grapemanca @greg_ashman
      My experience is that math is not even vaguely oriented with the average student’s life. Issue here could be pedagogy and/or curriculum?

      Tom Bennett‏ @tombennett71 Jul 3
      Replying to @mike_hengeveld @grapemanca @greg_ashman
      Why should it be relevant? Education takes us beyond the reach of our circumstances

      A common argument for teacher-led, broad curriculum is that students need to be lifted out of ignorance. Another point is that efficient problem solving requires a solid domain knowledge. While I agree with these points and they are supported in literature, I haven’t found that students retain much in our current “traditional” model. The reading I have done around PBL suggests that retention and concept mapping is improved with deeper exploration, but we sacrifice breadth. So I’ve been explaining our program to parents as “Instead of 10 things and remembering 1, we will cover 5 things and you will remember 4 of them.” I have no meaningful longitudinal data of my own to support this claim (!).

      1. Michael,

        That comment on your Twitter discussion “Why does it need to be relevant” made me twitch as I was reading it. There are so many students that are averse to school do to any number of circumstances and in order to win them over, the content needs to be presented in a relevant form; Maybe if its an accelerated AP Calculus class where the students are overjoyed and motivated to be there we can let this slip (we still shouldn’t).

        I’m not saying that the content can’t be taught without context and relevance, but in my experience it really helps more students want to understand.

        Baljeet

  3. Michael, I love your project idea!

    I had an amazing Physics 11 teacher that attempted to make the problems we were solving real and it has really stuck with me all these years. In the preliminary stages I wonder if students will understand the importance of small fins and subtlety of shape. I understand this is the process but if you find that they are not grasping it (or you need a hook) Top Gear (BBC) has a ton of clips on the effects of air resistance and car design. For example, Mclaren uses a rear wing that moves in order to help with braking and in an episode where one of the presenters drives a Nascar car he points out a small (maybe 2 inches tall) flap on the roof of the car that prevents it flipping in corners (Series 18 Episode 2).

    Looks like you are doing some pretty awesome work at your school!
    Baljeet

    1. Hey Baljeet,

      Thanks for the comments. Top Gear is a great show reference–thanks for the McLaren episode. I had not seen it. Myth Busters is a frequent visitor to my class as well. These shows are both definitely in the get ‘er done camp! The vision for our STEM program is still in development, but making actual stuff first and back-filling theory later has been a recent development that I find attractive. Messy development creates a concrete need for vocabulary and organizing concepts to lift things out of failure mode. It also seems to suit the teenage condition. 🙂

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