A collection of demonstrations and tutorial material on basic 1-dimensional kinematics, including explanations (text and graphics), problems, VRML demonstrations, and an interactive Java applet that simultaneously shows position, velocity, and acceleration graphs.
Type of Material:
Two applets require a VRML plugin for the browser. The recommended Cosmo plugin worked without effort (other than the download and simple installation) with Internet Explorer; the same cannot be said for Netscape Navigator 4.7.
Identify Major Learning Goals:
To help students understand and be able to describe motion in one dimension with words, formulas and graphs.
Target Student Population:
Prerequisite Knowledge or Skills:
Algebra and some introductory kinematics
Evaluation and Observation
The XVA Kinematics Graphs applet should be very helpful for self-study, and could also be used as a lecture demonstration. The section discussing slope and area of x, v, and a versus t graphs is useful, and not part of most similar Web materials.
The site is obviously in progress, with very limited coverage. The author uses a non-standard notation for displacement (d). The discussion on how to construct graphs is promised, but still missing.
General Comments on Quality: What is here is physically correct, but very limited. The two VRML applets show only uniform motion and speeding up at a constant rate, and are not worth the effort to download the plugin. The ability to move and rotate the graph adds little to the presentation. A simple java applet or even an animated gif would do the same with less chance of technical problems. The tutorial discussion, though good, is limited to the relationships between position and constant velocity graphs, and velocity and constant acceleration graphs. There is no discussion of the slope of curved graphs or the area under anything but constant value graphs. The organization of the material seems non-optimal. For example, the order of section 3 and 4 should probably be swapped. The XVA Kinematics Graphs tool is excellent for those who wish to develop tutorial material, but is used only sparingly.
Potential Effectiveness as a Teaching Tool
Recommended Uses for Material (used for Effectiveness Review): Tutorial and (limited) Homework. The XVA applet could be used for lecture/demo.
The XVA Kinematics Graphs applet is excellent (despite the wild colors). Discussions of slope and area of x, v, and a versus t graphs are good. The problems assign random numbers, and help may be sought for the incorrect answers.
The coverage is incomplete. The problems are simplistic. The structure of the site could be improved and the material could be more streamlined.
General Comments on Effectiveness: The tutorial discussions that are here are pretty good -- e.g., change in quantities ("What are deltas?") and slope and area of graphs. However, the discussion of slope is limited to positive straight-line graphs with positive slope, and the discussion of area is limited to constant-positive-value graphs. There is a large library of different kinematics cases (XVA Library), but there is a lot of repetition within the cases. More importantly, rather than presenting a lot of static cases, it would have been much more helpful (and a lot less written material to plough through) to present the cases in the form of questions for students to answer using XVA.
Ease of Use for Both Students and Faculty
This is an acceptable tutorial introducing student to the description of 1-dimensional motion. It has some very nice features, such as the x, v, and a versus t graphs, and the discussion of slope and area. The XVA applet is easy to use and understand.
It is difficult to get a coherent view of kinematics due to the incomplete coverage and confusing structure.
General Comments on Ease of Use: The site can be used as a tutorial that students explore on their own, or as a supplement to kinematics instruction, with the help of additional materials.