Improvement of the Introductory Physics Laboratories
March 23, 2001
Submitted by : Roger Rusack, Physics Faculty and Ben Speakman, Physics Student
Synopsis
All introductory courses in physics include laboratory instruction. In 1998 we proposed
to update our introductory physics courses that are taken by a large number of IT
undergraduates by introducing computer-assisted data-acquisition systems in the
laboratory part of the course. It enabled us to equip the eight teaching laboratories used
primarily for the instruction of IT students with computers that could be used to guide the
students through the hands-on work they were doing in a pedagogically sound manner.
This approach which had been developed in a collaboration between the Physics
Department and the Education Department with NSF funding, included the use of realtime video data collection which was analyzed by the student. The cost of setting up the
system was the development of the software and the purchase of computer equipment.
We are requesting funding for the coming three years to update and improve the
computer equipment in the labs, to improve and maintain the existing software and to
develop new software to be included as part of the existing package. While in the last
three years we have been transferring our teaching labs from manual to computer-assisted
data acquisition and analysis without modifying the fundamental teaching method, our
plan for the next three years is to replace and upgrade the computer equipment and to
introduce into the instructional environment a new teaching tool which, without
computers, would have been completely impossible. The new software will allow
students to test the physical parameters of the experiment with a simulation.
Introduction
Approximately 1200 IT students take the calculus based introductory physics course
each semester for a total of over 2400 IT student-semesters per year. These courses
include one two-hour laboratory section per week where the students obtain hands-on
experience of the physical world, leading to a better understanding of both mechanical
and electromagnetic interactions. Our teaching-lab rooms are designed to hold a
maximum of 15 students working in groups of 3, although they often have more.
Currently these two-hour laboratories operate from 8 am until 9 pm during the week and
on Saturday morning. Laboratory overcrowding was made worse by the switch to
semesters. Over the past 12 years we have been slowly improving the laboratory
experiences by modifying experiments so that they are more fully integrated into their
respective courses.
In the past three years we have introduced into all these teaching laboratory computers
for data-acquisition and data-presentation with funds from IT lower division students. As
this was primarily a modification of existing teaching methods we had to ensure that the
teaching environment was improved and not made worse. Appendix I contains a
summary of the student evaluations collected in the first year of the program. At this time
the software was less stable than it is now and the TA’s were less familiar with its
operation even so the net improvement to the student’s lab learning experience can be
seen in the responses to our questionnaire. In Appendix II we show a comparison
between evaluations given by students who were using the new labs and those using the
old ones.
As every week there about 1200 IT students using the teaching laboratories, it is essential
to have stable and reliable software and robust hardware. Our approach has been to
develop modular code using the NI LabView software, to make revisions during breaks
in the teaching and to beta test all new code in just one teaching laboratory before full
distribution. We will implement the changes proposed in this work following the same
procedure.
Project Description
The objectives of the program will be to have all of our teaching laboratories for the
Calculus based semester physics courses 1301/1302 and their honors equivalent
1401/1402 with computers running data-acquisition and simulation code. The computing
environment will be similar to what we have set up in the labs in the past three years. We
will replace all the monitors with LCD screens to save laboratory space taken up by the
bulkier CRT screens. We will update the computers and cameras to support modern
Firewire data streaming to improve the quality of the video data for the students.
Hardware Improvements:
We will replace all the computers in the labs with high-end PC’s. This will meet the
needs of the new simulation code and improve the current video processing. We will
enter the video stream on Firewire, or possibly some other high-speed data interface, to
overcome the problem of frame-skipping in the video input. Since we use the frame
number to estimate time this presents a problem which has proved challenging to
overcome in the software. With Firewire this will not be a problem.
We will replace all the 17” monitors at all the 52 stations with large flat screen monitors.
This will provide much more workspace for the students and more screen space to show
different windows and easier viewing by the students. We did not use these in the past
since the angular aperture was too small for the screen to be seen by more than one
student. Recent developments in commercially available screens has removed this
constraint. We will equip each lab with a LCD projector. We have found that the TA can
explain the experiments and software to the students more effectively if they can project
their terminal onto a screen with a LCD projector. In addition we need to provide a
budget for repair and maintenance of the computer equipment and the interfaces due to
the normal wear and tear. Software must also be maintained to keep up with changing
needs, changing hardware, and updated software systems.
The physics department will, as before, cover from instructional funds the cost of the new
experimental apparatus that will be needed as the program develops with common items,
like video cameras, will be covered on a 50-50 basis.
Software development:
The new simulation software is in the early stages of development. The idea is to allow
students to see the effect of changing variables not open to change in an actual lab, such
as friction-coefficients, air drag, etc. This will allow students to test ideas about the
sources of disagreement between between predictions and their data. The goal is to
produce frames of a simulated experiment, which can be used in the same analysis
system as the frames from a real experiment. Eventually this system may be put on the
world-wide-web.
The plan is to have a two-step process, with a Java program the students change physics
values and run the "virtual experiment" in real time. The real-time Java program uses
Java3D for its 3D graphics, and the Swing toolkit to implement the attendant GUI.
Although there are faster graphics packages, we expect Java3D to have adequate
performance, if the labs are equipped with 1GHz+ PCs. Students run the Java program
and adjust the various physics parameters, viewpoints, etc until they have a virtual
experiment they are happy with. When they wish to analyze their virtual experiment, they
push a button which produces a file containing the positions of the apparatus for each
frame, which can be analyzed like real data.
Our plan is to have a beta version of this code for one of our experiment groups by the
end of the summer ’01. We will install the code in one lab and run it there for the first
semester fixing problems as they are found. In the second year we will install code in all
the labs and continue to develop the software extending it to cover all the experiment sets
in the third year.
In addition to this exciting development program it is necessary to continue to improve
the current software. Modules need to be re-written to match the new software and code
that was developed early in the project needs to be cleaned up.
Evaluation:
As in previous years we are requesting a full-time TA (50%) to evaluate the benefits to
the student of this program. We are always concerned that by making these
improvements we are actually hindering the learning process. To avoid this, or at least
reduce the risk, that this will happen we will continue to monitor the students learning
and experience in the laboratories.
Students who will benefit:
Students taking the following courses will be the beneficiaries of this program:
Physics 1301/1302- A calculus based quantitative physics course for scientists and
engineers. 1200 IT students/semester. ( 6 lab rooms with 6 stations each).
Physics 1401/02/2403 - A calculus based quantitative physics course for honors students
in science and engineering. 100 IT students/semester. (2 lab rooms with 8 stations each).
Physics 2515/16 - An introduction to quantum physics laboratory for physics majors and
minors, also taken by chemistry and engineering majors. 50 students/sem (1 lab room
with 6 stations).
Hardware Budget:
Over the three year funding period we need to replace all of the 52 computer stations
which will not have sufficient power for the simulation code and which have begin to
show the wear and tear they experience in the lab. A station consists of a computer with
a data acquisition card and interface box. The cost of each station is $3100 not including
the flat-screen monitors. Included is the cost of the TA’s computer, one per lab., which
also acts as a server and printer. The breakdown of these costs is given Table [1].
Table 1. Cost Breakdown of the lab station.
Item
Cost
Computer 1 Ghz P3 or similar, with 400 MHz bus
$2000
Data Acquisition Card
$600
1/6 replacement printer
$250
Software Licenses
$250
Total
$3,100
In addition we need to budget about $500 for each station, which will be shared equally
with IT-instructional funds, for the replacement of the video cameras. Another cost is the
$156 pa recurring charge for the network services.
Personnel Requirements
In order to carry out this major program successfully the necessary personnel resources
must be included. The Physics department cannot support the staff necessary to carry out
such a program as this, without drastically affecting other parts of our educational
mission. We need a full-time staff person with the knowledge of hardware and software
to keep the computer system operating, due to the continuous use of the system and the
problems that would ensue if the system was down during the semester. We estimate this
to be at least $50K pa with benefits.
We will need additional personnel to write the simulation software. Our complete effort
estimates for the three years include the full-time staff person whose responsibility will
be to maintain and solve day-to-day problems with the 52 computer system. For the
simulation software we need to pay half-time programmer (P. Border) and a full-time
undergraduate assistant (R. Egeland) to write the code. For evaluation of the
modifications to the course we are requesting a full-time (50%) teaching assistant and to
make the course evaluations.
Schedule
In the first year we will replace all of our monitors with LCD displays, purchase eight
high-end PC’s (5 student stations, 1 TA station and two for development) to run the beta
version of the software in one of the labs. In the second year we will replace all the
computers in the remaining labs (44) and continue the software development. In the third
year we will continue the software development without making any hardware additions.
Funding profile
Table 2. Cost breakdown.
Item
AY01/02
AY02/03
AY03/04
Total
Software Maintenace
NTS networking charges
New Computer hardware
LCD projectors
Maintenace
Flat screen Monitors
Lab Equipment 50% split
Software Development
Contingency
$50,000
$8,112
$16,000
$36,000
$3,000
$100,000
$4,000
$45,000
$52,000
$8,112
$88,000
$12,000
$4,000
$55,000
$8,112
$22,000
$65,000
$10,000
$50,000
$15,000
$157,000
$24,336
$104,000
$48,000
$11,000
$100,000
$26,000
$160,000
$25,000
Total
$262,112
$261,112
$132,112
$655,336
$4,000
Appendix I
Student Attitude Data – Introductory Physics with Calculus
Questionnaire Data after second quarter, W 1999 (N=450).
Population ( Engineering 52%, C Sci 19%, Chemistry 3%, Physics 3%, Math 2%,
Biology 11%, Other 9%)
The student responses show a very positive attitude toward the laboratory and using
computers in them. This is especially noteworthy since introductory laboratories are not
typically held in high regard by students. Below are the statements that we asked
students to rate. The responses below are given as a percentage of the class agreeing (A),
disagreeing (D), or neutral (N) about each statement.
The following statement that highlights the primary function of the computer in the
laboratory:
Comparing our prediction equation to our collected data
helped me understand the relationship between our graphs
A
N
D
67
24
9
and the observed motion
We also wanted to know whether computers introduced any equipment difficulty into the
laboratory from the following statements.
A
66
Most of the time, the laboratory equipment worked well
N
22
D
11
Using computers in the physics laboratory makes it more
difficult to tell what is going on.
23
26
51
(A negative response is positive)
Computers helped take data quickly so that we could spend
more time on other parts of the lab
46
31
24
In addition we were interested in the student impression of the overall effect of the
laboratory on their education:
A
N
D
The lab problems helped me to understand the course concepts
60
22
17
My group worked well together on the lab problems
79
17
4
The laboratory sessions helped me learn how to solve problems
52
29
19
The laboratory was an important part of my
learning in this course
51
29
20
Appendix II
As we switched to computerized introductory laboratories in 1997 we compared half of
the class taking the laboratory using computers (C) and half of the class taking the
laboratory without computers (N). The following were the responses:
The lab problems helped me to understand the course concepts
C
N
A
N
D
49
50
28
26
23
24
The time in the lab was well-spent learning.
C
N
51
38
30
33
19
29
I look forward to using this equipment in lab next term
C
N
47
16
33
27
20
57