Circuits for Everyone: A ProblemBased Learning Approach

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Circuits for EveryoneA Problem-Based Learning
Approach
George Watson ghw_at_udel.edu Department of Physics
and Astronomy
University of Delaware
Fall Meeting of the Chesapeake Section
AAPT Tidewater Community College, Virginia Beach,
VA
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Silicon, Circuits, and the Digital Revolution
SCEN103 at the University of Delaware http//www.p
hysics.udel.edu/watson/scen103/
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The course SCEN103 in Spring 2000 was an Honors
colloquium designed to introduce first-year
students to some of the science behind high
technology.
Designed to promote scientific and computer
literacy and awareness, SCEN103 gives students an
opportunity to leverage their interests in
everyday devices and high-tech objects into a
study of fundamental science concepts. Live
demonstrations, in-class group explorations of
technology applications, and daily work with the
Internet are essential elements of SCEN103.
link
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A key feature of the writing-intensive work for
this colloquium was the students setup and
development of a personal website.
Working in small groups, students also created
websites devoted to science and technology
topics. This years colloquium was designed as a
pilot Pathways Course during the discussion of
General Education Reform at UD. Much of the
learning in Spring 2000 SCEN103 was done with
problem-based learning.
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Broad Course Objectives
Analyze simple electrical circuits to assess
their function and effectiveness.
State and describe fundamental scientific
principles underlying modern electronic devices.
Explain the basic operation of electrical
circuits, simple semiconductor devices, and
integrated circuits.
Identify the contributions of science and
technology to everyday life.
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Communicate technical ideas orally and in
writing. Evaluate the information content of
Internet resources. Use graphical and other
multimedia elements effectively in a webpage.
Create an informative and organized website
devoted to presenting a topic of technical
interest from various perspectives.
Access timely, relevant, and authoritative
information for problem solving. Construct
technical information into a logical framework
for decision making. Establish a frame of mind
where quantitative reasoning is embraced. Work
effectively in a group to solve complex problems.
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Problem-Based Learning in SCEN103
SCEN103 relies heavily on PBL with students
working collaboratively in groups to solve
real-world problems. Students learn to apply
simple scientific concepts, find and evaluate
scientific and technical information, and
communicate ideas about science and technology to
others. Discussions led by the course instructor,
plus supplementary lectures, help to give a
context and conceptual framework to the problems.
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Why PBL in SCEN103?
The rate of generation of new information in the
scientific and technical sectors is truly
staggering. Information becomes outdated rapidly
and is updated constantly much of what will be
needed to know in the workplace following
graduation has not been generated yet! Thus
identifying when new information is needed, where
to find it, how to analyze it, and how to
communicate it effectively are essential skills
to learn in college. An important result of PBL
is that while problems are used to identify what
to learn, the process of learning "how to learn"
is also developed. This method of instruction has
been chosen to help develop skills important for
success both in the students undergraduate
education and in their professional life
following graduation.
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What is effective learning in SCEN103?
Effective learning is much more than memorizing
information to answer questions on
examinations. Learning is a process that
culminates in the ability to ask the right
questions and frame good problems, to acquire
information and evaluate sources of information,
to critically investigate and solve problems,
to make choices among many alternatives,
to explain concepts to others (both orally and in
writing), and to generalize to new situations.
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Problem-Based Learning helps develop these
abilities!
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PBL 1
Crossed Circuits
Two roommates argue about perceived use of
electrical energy. Who should pay more towards
the utility bill?
Energy power x time
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"How long does it take you to dry your hair?
came Chris's scream from the kitchen. "I'm trying
to concentrate on my physics homework!" "Do you
want the answer as a fraction of a year? came
Pat's retort from the bathroom. "Then you can
have fun looking up the conversion to minutes in
the back of your textbook!" "You've been at it
for at least 20 minutes. You know, you should
have to pay extra toward the electric bill. I
bet you spend an hour a day drying your hair. I
think 5 extra each month would be about
right." "You've gotta be kidding me. With you and
your night light burning all night long, I bet
you use much more electricity than me! What are
you afraid of anyway?" "Yeah, but sometimes you
fall asleep with your TV blaring. I bet that uses
much more than my little night light." "Oh,
please! That only happens once a month. Your
Winnie-the-Pooh light is on every night!
Besides, how about your incessant showering. You
take at least twice as long in the shower as I
do. That must cost much more than running my hair
dryer. What do you do in there anyway?" Which
roommate should pay a utility premium, Pat or
Chris? How much extra?
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Lab 1
Hairdryers How much power?
Students bring in their hairdryers and test all
settings. A relationship is discovered among the
three circuit quantities while checking the
manufacturers claims.
Power current x voltage
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PBL 2
A San Francisco Treat
Electrical wiring plans are formulated for a
building conversion using floorplans from a This
Old House project.
Parallel circuits Household wiring Power ratings
of appliances
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Exercise 1
Electrical Energy Use in the World?
Student groups use the CIAs online World Fact
Book to accumulate regional electrical energy use
and investigate sources of discrepancies.
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Globalization for Pathways Course objective
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PBL 3
More Power!
Mark and Tim Allen rewire a toaster for more
power by using hairdryer parts.
Resistance and Ohms law
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Lab 2
Resistivity and Play-Doh
Students roll out cylinders of various diameters
and find a relationship among resistance and
geometric factors.
Resistance of a cylinder (wire)
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PBL 4
Spring Break Adventure
Students investigate the circuit concepts behind
the operation of two familiar battery testers.
Synthesis of cylinder resistance, Ohms law,
and Electrical power
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Lab 3
Batteries and Bulbs
Students work from the simplest possible circuit
to the challenging circuit on the left and its
companion on the right.
Series and parallel combinations
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Exercise 3
Penetration rates of major consumer products in
U.S. households
Historical aspects of electrical use
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PBL 5
Lights Out!
Students attempt to design a flashlight from a 6V
lantern bulb and two AAA cells that will last for
five hours.
Batteries and internal resistance Energy
capacity Circuit design
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Problem-Based Learning at the University of
Delaware
www.udel.edu/pbl
Institute for Transforming Undergraduate Education
www.udel.edu/itue