Project Topic
When an object moving in two dimensions experiences a force which is not parallel to its velocity, it moves along a curved path. There are several interesting cases: ballistics, rotation, circular motion (orbits), and harmonic motion.
Two key representational tools that aid problem solving in this domain are inertial reference frames and vectors. Using these tools, the student can decompose complex motion into component parts that can be examined separately. Non-inertial reference frames can help students understand the relationship between centripetal forces applied to and apparent centrifugal forces experienced by passengers in a vehicle rounding a sharp corner or enjoying a ride at the fair.
Students apply concepts learned while studying one-dimensional motion (position, velocity, acceleration, inertial mass, etc.) to the two-dimensional environment. The mathematics of rotary motion includes several key analogs with linear motion (e.g. linear/angular velocity, linear/angular acceleration, inertial mass/rotational inertia, force/torque).
Despite the near universal disdain of the GSE community for intelligent tutoring systems, I'm still convinced that standard curricula could be augmented by relatively simple hypertext-based review and self-assessment materials. Researchers here point to the limitations of AI techniques that try to assess the understanding of the individual student. They also rightly attack those who simply transfer paper materials on the computer screen. Is there no middle ground? Surely a hypertext-based system could be constructed that would have a clearer picture of student understanding than any high school Physics text.
Another significant advantage of such a system is that it could provide the scaffolding necessary for students to solve larger, more interesting problems than are typically found at the end of a textbook chapter. Students could apply what they've learned to real world engineering problems (e.g. "Is it possible to place a satellite in orbit so that it always stays over the same spot on the Earth's surface?") rather than simply mapping appropriate formulas onto cookie-cutter exercises. Hopefully this would both provide a clearer motivation for learning the concepts and guard against their compartmentalization into "knowledge useful for passing the Physics test."
Perhaps this kind of hypertext-based tutorial could be combined with simulation software like ThinkerTools so that in response to incorrect answers the system could suggest that the student design and conduct simulated experiments to help resolve the issues. In this way, the ThinkerTools curricular and assessment materials (currently xeroxed paper) could become a little more dynamic.
In summary, I think that tutorial materials of this kind could be part of a balanced breakfast, er science curriculum. Perhaps more importantly, they could be employed in a relatively non-intrusive manner for review and self-assessment of concepts covered via more traditional teaching methods. If one hopes to overcome pedagogical inertia, then I consider incremental change more practical than outright reform.
Physics Hypertext Site List - A bunch of links to college Physics courses conducted on or supplemented by the web.
Rotational Motion Tutorial - A complete tutorial on rotational motion. There are a few self-test questions, but you just get a "correct!" or "no, you should have done it this way..." answer, rather than having different information and/or questions provided in response to the specific answer given.
The Interactive Physics Textbook - Doesn't seem very interactive to me, but I didn't try the Java version.
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© 1997, Chris Schneider. All Rights Reserved World Wide.
Last updated 14 February 1997