Asynchronous Collaborative Investigations

These investigations are based on hands-on observations and collaborative analysis.

Materials for conducting these investigations will be mailed when the request is received by the instructor, according to instructions provided under Course Materials.

You will begin each investigation by setting up and observing a simple physical system and submitting your qualitative and quantitative observations.  Other students will be doing the same.

After the deadline for submitting observations, all submissions will be made available to all participants in a special portfolio page.

Participants will then analyze \observations using the tools and techniques developed in course assignments.  Every participant will analyze his or her own observations, and will be assigned to also analyze those of one other participant.  Results will be compared and discussion will ensue.

After another deadline all submitted work will be made available to everyone, and another round of discussion and analysis will follow.

Standards of etiquette, as previously defined, will be followed.  The instructor will mediate the exchange of information.

Discussion boards may at some point be opened, depending on the quality of interaction and the instructor's assessment of the potential benefit of doing so.

First investigation:

Rubber band length vs. tension.

Complete instructions will be provided with your materials.

You will suspend a chain of two rubber bands connected by paper clips, with the lower of the two supporting a plastic bag which will be partially filled with water, one teaspoon at a time.  The lengths of the two rubber bands will be measured with every other teaspoon.  A teaspoon of water will be taken to have a weight of 0.5 Newton.  This is pretty close to accurate, but people will use different spoons, most of which won't be regulation teaspoons, so we won't have a high level of uniformity between observers, though there will probably be some reasonable level of uniformity.

You will also observe how the lengths of the two rubber bands vary when they are in opposition.

From the data taken it will be possible to construct a graph of the weight suspended vs. the length of the rubber band, for each rubber band.  Interpreting this as a trapezoidal graph, we will investigate the meanings of various aspects of the graph.

We will also model the graph using a polynomial of appropriate degree.

You'll get more detailed instructions for subsequent steps after you've submitted your observations.

Suspend

send materials

distribution of errors

flow expt

rubber band force vs. length, definition of energy, calculation of energy

marble down incline, optimization

pendulum period vs. length

rubber band chain supporting mass:  period vs. length of chain

kinetic or orbital simulation for PC users

sandpiles

etc.