Physics Challenge Laboratories

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Robert W. Arts, Ph.D.
Professor of Education & Physics
University of Pikeville
Pikeville, KY
Presented at the Spring Meeting of the Kentucky
Association of Physics Teachers
Bowling Green, KY, March 17, 2012
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“…basically an experiment where physics
students attempt to obtain a specific outcome
under some sort of constraint conditions set by
the instructor. The students must work within the
constraints set by the instructor and they must
work only with the equipment given by the
instructor" (Jones, TPT, 2009).
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I have been very dissatisfied with many of the
traditional cookbook laboratories offered in
physics. Additionally, I have experimented with a
number of alternative laboratory practices such as
inquiry based, activity-based, and project-based;
none of which I really felt connected with. As
such, I have taken to incorporate a number of
"challenge" laboratory activities in each semester of
my general physics courses for science majors.
Additionally, we have recently added the
requirement of General Physics I & II to the middle
grades science education major. Their ability to
use applied knowledge and to think ‘outside the
box’ is paramount to their success in science
courses.
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In general, all challenge labs are graded in two
parts
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The Theory: The laboratory notes taken during the
challenge outlining the method/course of action
taken. This includes, but is not limited to, a
procedure, a correctly illustrated free-body diagram
and a list/explanation of the equations used.
The Experiment: Actual experimental results
(numerical value, wiring diagram, etc.).
Each group submits a final report and as such each
member receives the same grade for the work
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Challenge lab instructions are designed to be clear and simple.
As a result, students clearly understand what they need to
accomplish and set out immediately trying to solve the
problem.
Challenge labs force students to deal with many of their
misconceptions in a fun and interesting way.
If their physics is wrong, they get instant feedback from their
experimental trials. You can allow a group to make a second
attempt for a reduced grade, if applicable.
Student motivation to do well on these challenges is always
high. This generates a great deal of vigorous discussion and
various attempts to solve the problem on paper prior to
attempting an experimental run.
The students converge on correct answers as they discuss their
ideas and usually the good physics wins. When any group is
ready for an experimental attempt, every other group stops to
watch the action. The lab generally fills with cheering students
when a groups experimental trial goes well!
There is something about this competition aspect of these
challenge labs that students really seem to like.
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It has not been possible to compare previous
year’s lab grades to labs which have
incorporated these challenges
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Apples to Oranges
However, comparative results of quiz and
exam scores for these two groups seem to
suggest that those students exposed to the
challenge labs have a greater degree of higher
order thinking and as a result a higher score on
these assessments.
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Time will tell as more data is collected
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“They were stressful at the time but after the
fact I knew I knew what I was talking about
and felt more confident from it.”
“At the time I did not like the challenges.
Now, having finished the course, I see the
value in what we did in terms of my ability to
apply what I have learned as opposed to
simple regurgitating memorized information.”
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The purpose of this challenge laboratory is to
match a series of motion graphs. The challenge
is designed to further an understanding of how
to construct and interpret graphs of position or
velocity versus time.
Comparative
integration yields
approximately a
1% difference
Comparative
integration yields
approximately a
6% difference
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The inclination angle of the track (q), the mass of the cart
(MC), and the distance (d) between the photogates are all
fixed—they have been and cannot be changed. Groups
draw both a station number and target time. The challenge
is to determine, theoretically, the hanging mass (M)
required to produce the target time and to experimentally
verify that prediction. The challenge is fairly open ended
and each group is free to attack the problem any way that
they see fit.
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Provided is a configuration of
six light bulbs (one 15W, two
40W, two 75W, and one 100W).
The bulbs are arranged at the
points of a six-pointed star on
the top of the box. The triangles
of the star points are color
coded (Red, Orange, Yellow,
Green, Blue, and Violet) to assist
in describing the system. Each
lamp socket is also equipped
with its own on-off switch.
The Task: To identify how the
six light bulbs are connected
together (without opening the
box.).
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Challenge labs and other experiences like it are an
invaluable part of learning physics.
The experience teaches physics students how to solve
problems and to apply physics to laboratory phenomena.
Many common laboratory experiments and physics
problems can be turned into challenge labs.
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I currently have 8 challenge labs each year (1/3 of the total labs
completed) that are interwoven with traditional laboratories.
The teaching advantages to using lab challenges are
numerous:
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Motivation for students
Creates authentic learning experiences
No complex lab handouts for students to read; yet students must
use applied knowledge from lecture and pervious laboratory
experiences in order to solve the challenge
Easy grading
No laboratory report to complete at home
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