Each teacher has to decide whether each experiment succeeds best (promotes
learning) by computerizing data acquisition or by more manual data
acquisition. Here are some of the ways I make that decision.
(1) I use a computer when data must be recorded faster than I can record
them. In this mode, a computer is not really different than a fast chart
recorder or a storage oscilloscope. Whether I use a recorder, scope, or
computer just depends upon what seems easier for the particular experiment.
For some experiments I have tried all three, and I don't have strong
pedagogical evidence to prefer one to the other.
Example: A force transducer yields force (voltage) versus time data during a
collision. The goal is to study the impulse and relate it to the change in
momentum.
(2) I use a computer if I need to collect a very large number of data points
and/or if this occurs over a long period of time. I don't feel guilty
having students collect 10 to 50 points manually over an hour. But writing
down over 50 points, or making them stay up all night, is not very
productive. I don't have good physics examples of this except for
experiments requiring long counting periods (e.g. measuring background
radiation levels). Environmental data acquisition is a something that comes
to mind here.
(3) I tend to apply KISS in most other instances. For example, I use
photo-gate timers (non-computer based) for air track experiments because I
want students to get a feel for the data they are collecting, and I
certainly want them to calculate velocity and acceleration themselves...
that is my goal for these labs.
Additionally, I have students use computers for word processing (Word) and
for data processing (Excel) and I encourage them to use various graphing
program. (Although I keep threatening to have them graph some things by
hand so they'll understand what the software is doing for them.)
For my year-long calculus based physics class we do approximately 24
experiments over the course of the year. Students acquire data with the
computer in roughly 5 of these experiments.
On the other hand, in my modern physics class (one semester, 12 experiments)
we acquire data with the computer 8 or 9 times.
Michael D. Edmiston, Ph.D. Phone/voice-mail: 419-358-3270
Professor of Chemistry & Physics FAX: 419-358-3323
Chairman, Science Department E-Mail edmiston@bluffton.edu
Bluffton College
280 West College Avenue
Bluffton, OH 45817