BLACKOUTS
INSIDE THE GRID:
Where Does Electricity
Come From?
Tara Kotheimer
Carl Sandburg High School
District 230
IIT Research Mentor: Dr. Alexander Flueck
Summer 2006
Table of Contents
Activity 1: What is an Engineer? .................................................................................... 3
Materials ............................................................................................................... 6
Presentation: What is an Engineer? ................................................................... 18
Module Pretest .................................................................................................................
8
Pre/Post Test Rubric ........................................................................................................ 12
Pre/Post Test Assessment Matrix ................................................................................... 15
Activity 2: Behind the Plug – Circuits and Ohm’s Law ...............................................
Materials ...............................................................................................................
Presentation: Into the Grid – A Study of the Power Grid ...............................
Ohm’s Law: Power and Energy Problems ........................................................
Ohm’s Law: Power and Energy Problems Rubric ...........................................
Presentation: Circuits ..........................................................................................
Circuits Problem Set ............................................................................................
Circuits Problem Set Rubric ...............................................................................
Ohm’s Law Circuit Lab – Pre-lab Activity .......................................................
Ohm’s Law Circuit Lab ......................................................................................
19
21
22
23
26
33
34
37
40
43
Activity 3: Ohm’s Lab / Circuit Lab .............................................................................. 52
Activity 4: Distribution Grid...........................................................................................
Materials ...............................................................................................................
Presentation: Circuits and Safety .......................................................................
Electrical Safety Worksheet ................................................................................
Electrical Safety Worksheet Rubric ...................................................................
55
57
58
59
61
Activity 5: Power Plant ....................................................................................................
Materials ...............................................................................................................
Presentation: Inside the Power Plant .................................................................
Electromagnetism Induction Lab .......................................................................
Electromagnetism Induction Lab Rubric ..........................................................
63
65
66
67
70
Activity 6: Inside the Generator .....................................................................................
Materials ...............................................................................................................
Presentation: Electromagnetism.........................................................................
Electromagnetism Worksheet .............................................................................
Electromagnetism Worksheet Rubric ................................................................
71
73
74
75
77
i
Activity 7: The Generator ............................................................................................... 78
Materials ............................................................................................................... 82
Electric Generator ............................................................................................... 83
Presentation: Engineering and Science .......................................................................... 96
Activity 8: Generators and Transformers ..................................................................... 97
Materials ............................................................................................................... 99
Presentation: Generators and Transformers ....................................................100
Generator and Transformer Worksheet ...........................................................101
Generator and Transformer Worksheet Rubric ..............................................103
Activity 9: Power Sources ...............................................................................................105
Power Source Research Project ..........................................................................108
Presentation Rubric .............................................................................................109
Lab Sheet ..............................................................................................................110
Evaluation Matrix ................................................................................................113
Types of Power Plants .........................................................................................115
Engineering Code of Ethics .............................................................................................116
Module Post Test ..............................................................................................................117
ii
Activity #1: What is Engineering?
3
Teacher’s Notes
Objective: Students will explore the differences between science and engineering, expand their
knowledge of the many different branches of engineering and be exposed to some frequently
asked questions concerning the study and practice of engineering.
Time Requirement: Pretest 20minutes: Lesson 28 minutes
Materials Needed: - Pretest
- What is Engineering Brainstorm Worksheet (1 for each student)
- What is Engineering PowerPoint?
- OPTIONS Worksheet (1 for each student)
 Class will begin with the module pretest. Students will have 20 minutes to complete this
assignment. They are to work alone. Be sure to encourage the students to answer all the
questions, even if it is their best guess. Students will most likely not know many of the
answers to the pretest, thus the allotted 20 minutes may be too long. Once every student
is done, collect the pretest and begin the engineering lesson.
 Begin by passing out Brainstorming Worksheet to every student. Have student complete
the worksheet individually. (3 minutes).
 Have students share their answers verbally with the rest of the class. (3 minutes).
 Present What is an Engineer? PowerPoint to the students. Make the distinction between
science and engineering. Provide an overview of some of the different areas of
engineering. Discuss salaries, education, job description, and sites where students can get
further information on engineering careers.(15 minutes)
 Pass out the OPTIONS Worksheet. They are to keep this as reference material.
 Show class unlabeled pictures of 2003 Blackout and ask them to identify what day in
American History is depicted by these images. (2 minutes)
 Students will most likely guess that the pictures are from 9/11 or a natural disaster such
as Hurricane Katrina. Explain that these are images from the 2003 North American
Blackout. Explain what each image details. Explain to students that engineers were the
people responsible for solving this problem, thus tying this attention getter to the day’s
earlier material.
(3 minutes)
 Finally, ask students to answer three questions for homework.
1. What is the power Grid
2. How is the power grid organized
3. What causes the power grid to fail during a blackout?
4
ASSESSMENT:
 Pretest
RESOURCES
http://www.tryengineering.org
http://www.csun.edu/~rseki/teaching/100b/QMC18.htm
http://www.gcsescience.com
http://en.wikipedia.org
http://www.bls.gov/oco/oco1002.htm
“ Engineering: How is it related to Science ,Technology, math, and Society?”
Dr. Alexander Flueck. Illinois Institute of Technology
http://www.engineeringk12.org/students/default.html
http://www.cbc.ca/news/background/poweroutage/numbers.html
http://www.time.com/
5
Activity #1: What is Engineering?
Materials
6
Engineers Versus Scientist Brainstorm Worksheet
1)
What does an engineer do?
2)
How does an engineer influence your everyday life?
3)
What does a scientist do?
4)
How does a scientist influence your everyday life?
Taken from “ Mathicity” Stacy Dunn Illinois Institute of Te chnology
7
PRETEST
This test is not for a grade. This test will simply show me how much you know about
an upcoming topic! Answer each of the questions to the best of your ability. There are no
right or wrong answers.
1. What does an engineer do?
2. How are scientists and engineers different?
3. Your boss at the restaurant has decided to add a new item to the menu, salad. He
wants you to write a procedure for making a salad so that he can give it to the
cooks.
.
a. . What would your general process for making a salad look like?
b. Does making a salad require a design process? Why or why not?
c. Will everyone who comes up with a process for making a salad have
the same process?
8
4. If you are a consumer and order a salad at a restaurant would you want there to be
a set of rules or standards for making your salad? Why or why not?
5.Do you think engineers should follow a set of guidelines or rules while doing their
respective jobs? Why or why not?
6. Where does electricity come from?
7. What is 1 Ω equivalent to?
a.
1 J/s
b.
1 W/A
c.
1 VúA
d.
1 V/A
8. If the resistance in a constant voltage circuit is doubled, the power dissipated by that
circuit will
a.
increase by a factor of two.
b.
increase by a factor of four.
c.
decrease to one-half its original value.
d.
decrease to one-fourth its original value.
9. What is the Circuit Symbol for a Battery?
9
10. . What type of meter measures Current?
11. . How is the meter which measures Current connected in Series or Parallel?
12. Which Equation connects Resistance, Current and Voltage?
13. Draw a Circuit with three Resistors connected in Series.
14. Draw a Circuit with three Resistors connected in Parallel.
15. Draw the Shape of a Magnetic Field around a Bar Magnet.
16. How can a Straight Wire produce a Magnetic Field?
17. What does a Circuit Breaker do?
18. Where in the National Grid is induced current used?
10
19. What is the National Grid?
20. What does a Power Station do?
21. Give two Advantages of Nuclear Power.
22. Give one Disadvantage of Hydroelectric Power.
11
Pre/Post Test Rubric
Question
1
0 points
No response
2
No response
3a
No response
or answers no
Answers yes, but
no example
3b
No response
Answers yes, but
no example
3c
No response
Answers no, but
no explanation
4
No response
or answers no
5
No response
or answers no
6
No response
or completely
off track no
7
8
9
10
11
12
13
No answer
No response
or answers no
1 point
Attempted,
mentions science
or math, but way
off base.
2 points
Close to the
correct answer,
but not all the
way there.
Gives a brief
comparison
Answers yes,
gives a vague
description
Answers yes.
But explanation
is not well
thought out
Answers no, but
explanation is
not well thought
out
Yes but no
reason
Answers yes but
explanation
unclear
.
Attempts to draw
symbol but it is
not correct
Makes an attempt
at drawing a
circuit, but
symbols are not
correct
12
Symbol is
slightly incorrect
Draws a circuit
with correct
symbols for
battery and
resistor
3 points
Mentions problem
solving and designing
things for society.
Gives many reasons or
examples
Answers yes, is specific
in description
Answers yes and gives
a well thought out
answer
Answers no and gives a
well thought out
explanation
Answers yes with a
reasonable answer such
as must use clean
utensils
Answers yes and gives
a good explanation
why
Mentions generators or
solar energy,
Letter D
Letter C
Correctly identifies
battery symbol
ammeter
series.
V=IR
Correctly draws a
circuit, symbols for a
battery and resistors are
correct, and resistors
are correctly arranged
in series
14
No
response
or answers
no
15
No
response
Makes an attempt
at drawing a
circuit, but
symbols are not
correct
Draws a magnet
with north and
south labeled
Draws a circuit with
correct symbols for
battery and resistor
Draws a magnet with
north and south
labeled and attempts
to draw field lines
16
17
No
response
18
No
response
No
response
It opens up
Generator or
transformer
Explains that is an
organization of
elements that
provides electricity
20
No
response
Generates
electricity
Changes mechanical
energy into electrical
energy
21
No
response
or answers
no
No
response
Answers yes but
gives no
explanation
Answers yes but
explanation unclear
Identifies power plant,
transmission lines, and
distributions lines in the
organization responsible for
providing electricity
Converts a resource into
mechanical energy and then
converts the mechanical
energy into electrical
energy via a generator
Answers yes and gives a
good explanation why
Provides and
answer that is not
well organized and
explained
Correctly identifies a
disadvantage
Correctly identifies and
explains a disadvantage
19
22
Explains that it is
the source of
electricity
It opens up when it
detects too much
current
Correctly draws a circuit,
symbols for a battery and
resistors are correct, and
resistors are correctly
arranged in parallel
Draws a magnet with field
lines originating from north
and bending around to the
south
If it has current running
through it
It detects the level of
current and it opens when
too much current its
detected, thereby preventing
fire hazards
Generator and transformer
13
STATE GOAL 11: Know and apply the concepts, principles
and processes of scientific inquiry and technological design
to investigate questions, conduct experiments, and solve
problems.
 STATE GOAL 11.A.5a: Formulate hypotheses
referencing prior research and knowledge.
 STATE GOAL11.B.5a: Identify a design problem that
has practical applications and propose possible
solutions considering such constraints as available
tools, materials, time, and cost.
 STATE GOAL11.B.5b: Select criteria for successful
design solution to the identified problem.
 STATE GOAL11.B. 5c: Build and test different models
or simulations of the design solution using suitable
materials, tools and technology.
 STATE GOAL11.B.5d: Choose a model and refine its
design based on the test results.
 STATE GOAL 11.B.5e: Apply established criteria to
evaluate the suitability, acceptability, benefits,
drawbacks and consequences for the tested design
solution and recommend modifications and
refinements.
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and motion and
the interactions between them and principles that explain
them.
STATE GOAL 13: Understand the relationships among
science, technology and society in historical and
contemporary contexts.
 STATE GOAL13.B.3c Describe how occupations use
scientific and technological.
14
Pre/Post Test Assessment Matrix
Question
Number
1
2
3a
3b
3c
4
5
6
Illinois State Learning Standards
13.B.3c Describe how occupations use
scientific and technological knowledge and
skills.
STATE GOAL 11: Understand the processes
of scientific inquiry and technological design
to investigate questions, conduct experiments
and solve problems
. STATE GOAL 11: Understand the
processes of scientific inquiry and
technological design to investigate questions,
conduct experiments and solve problems
STATE GOAL 11: Understand the processes
of scientific inquiry and technological design
to investigate questions, conduct experiments
and solve problems
STATE GOAL 11: Understand the processes
of scientific inquiry and technological design
to investigate questions, conduct experiments
and solve problems.
STATE GOAL 11: Understand the processes
of scientific inquiry and technological design
to investigate questions, conduct experiments
and solve problems.
STATE GOAL 11: Understand the processes
of scientific inquiry and technological design
to investigate questions, conduct experiments
and solve problems.
STATE GOAL 12: Know and apply the
concepts and describes properties of matter,
energy, force and motion and the interactions
between them and principles that explain
them
15
C
O
N
T
E
N
T
Problem
Solving /
Design Ethics
Scientific
Inquiry
X
X
X
X
X
X
X
X
X
7
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
.
X
8
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
X
9
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
.
X
10
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
.
X
11
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
X
12
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
13
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
16
X
X
X
X
X
X
14
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
15
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
16
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
17
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
18
STATE GOAL 12: Know and apply the concepts and
describes properties of matter, energy, force and
motion and the interactions between them and
principles that explain them
X
X
X
X
X
X
X
X
X
19
20
21
22
STATE GOAL 13: Understand the relationships
among science, technology and society in historical
and contemporary contexts
STATE GOAL 13: Understand the relationships
among science, technology and society in historical
and contemporary contexts
STATE GOAL 11: Understand the processes of
scientific inquiry and technological design to
investigate questions, conduct experiments and solve
problems
STATE GOAL 13: Understand the relationships
among science, technology and society in historical
and contemporary contexts
17
X
X
X
X
Presentation:
What is an Engineer?
18
DAY 2 Of Module
Activity #2: Behind the Plug: Circuits and
Ohm’s Law
19
Teacher’s Notes
Objective: Students will expand their knowledge of how the power grid is organized. They will
also explore the relationships between voltage, current, resistances,.
Time Requirement: 48 minutes
Materials Needed: - “The Day The Lights Went Out” PowerPoint
- The Blackout of 2003 Article (1 for each student)
**** This article can be found at the following website
www.eia.doe.gov/kids/classactivities/Blackout2003IntSec.pdf
- Ohm’s Law Power and Energy Problem Set (1 for each student)
- Student Equation Sheet(1 for each student)
Class Activities
 Class will begin with the teacher asking the student to report the result of their research,
regarding what the power grid is, how it is organized and the causes of a blackout, to the
class. As the students pose various scenarios, the teacher will utilize the first three slides
on the PowerPoint presentation, to help the students visualize where the problems
occurred in the grid ( 5 minutes)
 The teacher will then hand out the Blackout of 2003 article to the students. This should
be used as a reference worksheet. Students will be responsible for reading this material
prior to the design activity and final posttest evaluation.
 Students will take notes as the teacher reviews the equations and concepts for voltage,
current, resistance, and Ohm’s Law, power and energy (15 minutes)
 The teacher will hand out the Ohm’s Law Power and Energy Problem Set and equation
sheet. The teacher will model how-to solve the first three problems on the board. The
students will then work in groups of three to complete the remaining problems (15
minutes)
 Students will share their answers on the dry erase board. Students are allowed to make
corrections to their problem sets in a different color ink. The teacher will collect these
problem sets at the conclusion of this activity. (13 minutes)
Assessment:
 Teacher’s qualitative assessment of student answers to three questions regarding the
grid organization and causes of blackouts
 Ohm’s Law Problem Set
 Teacher observation of students ability to work in groups to complete worksheet
Resources
http://www.glenbrook.k12.il.us/GBSSCI/PHYS/CLASS/circuits/u9l1a.html
http://people.howstuffworks.com/search.php
www.eia.doe.gov/kids/classactivities/Blackout2003IntSec.pdf
20
ACTIVITY #2: Behind The Plug: Circuits
and Ohm’s Law: Materials
21
Presentation
INTO THE GRID: A Study of the Power Grid
22
OHMS’ LAW POWER AND ENERGY
PROBLEMS
Use the appropriate equations to solve the following problems. Be sure to show all of you work.
Do not forget Sig Figs and unit!
SAMPLE PROBLEMS
A nine volt battery supplies power to a cordless curling iron with a resistance of 18
ohms. How much current is flowing through the curling iron?
How many amperes flow through a 60 Watt light bulb at 120 Volts?
Jack often leaves household appliances on for no good reason (at least according to his
parents). His family pays 10¢/kilowatt-hour (i.e., $.10/kW•hr) for their electrical energy.
Express your understanding of the relationship between power, electrical energy, time, and
costs by filling in the table below.
Power Rating(Watt) Time(hrs) Energy Used(kilowatt-hour)Costs(cents)Costs($)
60 Watt Bulb
1
0.060 kW•hr
0.6 ¢
$0.006
60 Watt Bulb
4
120 Watt Bulb
2
100 Watt Bulb
10 kW-hr
60 Watt Bulb
1000 ¢
$10
100
60 kW-hr
23
1. An electrical device has a resistance of 3.0 . If a current of 4.0 amps flows through it,
how much voltage is applied across the device?
2. When a voltage of 120 V is impressed across an electric heater, a current of 10.0 amps
flows through the heater. What is the resistance of the heater?
3. A flashlight that is powered by 3.00 Volts and uses a bulb with a resistance of 60 ohms .
What is the current that flows through the bulb?
4. Use the Ohm's law equation to determine the missing values in the following circuits.
http://www.glenbrook.k12.il.us/GBSSCI/PHYS/CLASS/circuits/u9l1a.html
24
5. Calculate the resistance and the current of a 1500.0-Watt electric hair dryer plugged into a US
household outlet.
6. The sticker on a compact disc player says that it draws 288 mA of current when powered by a
9.0 Volt battery. What is the power (in Watts) of the CD player?
7. Your 60.0-Watt light bulb is plugged into a 110-Volt household outlet and left on for 3 hours.
The utility company charges you $0.11 per kiloWatt•hr. How much will this cost?
25
OHMS’ LAW POWER AND ENERGY
PROBLEMS
RUBRIC
Use the appropriate equations to solve the following problems. Be sure to show all of you work.
Do not forget Sig Figs and unit!
SAMPLE PROBLEMS
A nine volt battery supplies power to a cordless curling iron with a resistance of 18
ohms. How much current is flowing through the curling iron?
V=IR
.5ohms
How many amperes flow through a 60 Watt light bulb at 120 Volts?
P= IV
.5A
Jack often leaves household appliances on for no good reason (at least according to his
parents). His family pays 10¢/kilowatt-hour (i.e., $.10/kW•hr) for their electrical energy.
Express your understanding of the relationship between power, electrical energy, time, and
costs by filling in the table below.
Power Rating(Watt) Time(hrs) Energy Used(kilowatt-hour)Costs(cents)Costs($)
60 Watt Bulb
1
0.060 kW•hr
0.6 ¢
$0.006
60 Watt Bulb
4
.24
2.4
.024
120 Watt Bulb
2
.24
2.4
.024
100 Watt Bulb
100
10 kW-hr
100
1.00
60 Watt Bulb
167
10
1000 ¢
$10
600
100
60 kW-hr
600
6.00
26
1. An electrical device has a resistance of 3.0 . If a current of 4.0 amps flows through it,
how much voltage is applied across the device?
V=IR
12V
2. When a voltage of 120 V is impressed across an electric heater, a current of 10.0 amps
flows through the heater. What is the resistance of the heater?
V=IR
12 ohms
3. A flashlight that is powered by 3.00 Volts and uses a bulb with a resistance of 60 ohms .
What is the current that flows through the bulb?
V=IR
.05 A
4. Use the Ohm's law equation to determine the missing values in the following circuits.
1st diagram R=3ohms I = 2 amps
2nd diagram V = 6v R = 6 ohms
3rd diagram V= 4V I = 2 A
4th doiagram V = 2V
5. Calculate the resistance and the current of a 1500.0-Watt electric hair dryer plugged into a US
household outlet.
P=V2/R = 9.6 ohms
6. The sticker on a compact disc player says that it draws 288 mA of current when powered by a
9.0 Volt battery. What is the power (in Watts) of the CD player?
P=IV 2.6W
7. Your 60.0-Watt light bulb is plugged into a 110-Volt household outlet and left on for 3 hours.
The utility company charges you $0.11 per kiloWatt•hr. How much will this cost?
E=PT $.0198
27
Quantity
Symbol
Potential Difference
(a.k.a. voltage)
V
Equation(s)
V=I•R
Standard Metric
Other Units
Unit
Volt (V)
J/C
I
I=Q/t
I= V/R
Amperes (A)
Amps or C / s
or V /
Power
P
P= E/t
P=IV
P=I2R
P=V2/R
Watt (W)
J/s
Resistance
R
R=
Ohm (
V/A
Energy
E or
Current
PE
V/I
Joule (J)
E=P•t
28
)
V • C or
W
Day 3 of module
ACTIVITY 2: Behind The Plug:
Circuits and Ohm’s Law
29
Teacher’s Notes
Objective: Students will expand their knowledge of how circuits are organized into series and
parallel. They will evaluate the changes in voltage, current, and resistances in these circuits.
Lastly, they will gain a greater understanding of how electrons move in DC and AC circuits.
Time Requirement: 48 minutes
Materials Needed: - Bicycle Tire
- Circuit PowerPoint Presentation
- Ohm’s Law Lab(1 for each student)
Class Activities
 Class will begin with the teacher breaking the students into groups of two. Each lab
groups should be given a lab set up with a battery pack, 2 D batteries, 5 low voltage light
bulbs, and alligator clips. The teacher will ask the students to hook the light bulbs up in
any manner they wish. Once they are done they must answer the following questions.
(10 minutes)
1. Make a diagram of your circuit. You may use any symbols they want to represent the
circuit elements.
2. Is there more than one way to organize your circuit? If so, please provide a second
drawing of this organization.
3. Do you think the organization of a circuit effects variable such as voltage, current, and
resistance? Explain.
4. How fast do you think electrons flow through your circuit? Do the electrons always
move in this manner and at this speed?

Once the students have completed this activity the teacher will ask them to share
their results. Students should realize through class discussion that there is a
difference in the voltage, current, and resistance of the circuits and that these
differences arise from the manner on which the circuit is wired. The question
regarding electron flow is dealt with in the first few slides of the presentation.
The teacher should ask students to share their ideas on this concept and then
move into the presentation and bicycle tire demonstration. ( 5 minutes)

The Teacher will then have the students take notes as they present the Circuit
PowerPoint Presentation. The first few slides of the presentation are dedicated
to the flow of electrons in a circuit. The teacher will need the bicycle tire for
this demo. Sin the tire with one hand. Explain to the students how the
mechanical energy provided by your hand is transmitted almost instantly to all
parts of the wheel's rim. Point out that the wheel itself didn't move very fast.
“The rubber of the wheel is like the electrons in a wire. Electrical energy is like
the "jerk," the mechanical energy-wave which you sent to all parts of the wheel
when you gave it a spin. Mechanical energy moves incredibly quickly to all
parts of the wheel, but the wheel's atoms didn't have to travel rapidly in order
for this to happen” "ELECTRICITY" MISCONCEPTIONS IN K-6
TEXTBOOKS - - -William J. Beaty Once this part of the demonstration has been
explained, have a student come up and place their hand, gently against the side
30
of the wheel farthest from where your hand is causing the spin. Ask them how
their hand feels as they hold it there. They should say that their hand is getting
warm. Ask the students to explain what is happening. They should be able to
explain that the mechanical energy of the wheel is being converted to heat
energy as a result of friction. Parallel this to what happens with resistors in a
circuit. Thus, far the demonstration has dealt with DC current, but what about
AC? The electrons do not move, rather they vibrate. With one hand rock the
wheel back and forth, being careful NOT to let it spin. Again have the student
hold their hand on the opposite side of the wheel. They should experience the
same effect. Explain that in AC current the flow is changing directions every
second , much in the same way the mechanical energy of your hand does.(5
minutes)

The teacher should continue on with the PowerPoint. Be careful to point out
attachment of voltmeters and ammeters. Also make sure the students take down
the necessary equations ( 15 minutes)

The teacher will then hand out a copy of the circuit worksheet to all of the
students. The teacher will model how to solve the first two problems. Students
will then work in groups of three to complete the remaining problems. The
answers to these problems will be reviewed and collected at the onset of the
next day’s lesson ( 10-13 minutes)
Students will be given a copy of the lab “Ohm’s Law/ Circuits” and asked to
complete the prelab activity as well as read the lab for tomorrow’s class

Assessment



Teacher’s qualitative assessment of student performance
Circuit Problem Set
Ohm’s Law Lab and Pre-lab activity
Resources









"ELECTRICITY" MISCONCEPTIONS IN K-6 TEXTBOOKS - - -William J.
Beaty
http://en.wikipedia.org/wiki/Series_and_parallel_circuits
http://physics.bu.edu/py106/notes/Circuits.html
http://www.glenbrook.k12.il.us/gbssci/phys/Class/circuits/u9l4d.html
http://www.csun.edu/~gsl05670/labs/circuits_ser_par.htm
Physics: Principles and Problems. Paul Zitzewitz and Craig Kramer
http://www.csun.edu/~gsl05670/labs/circuits_ser_par.htm
http://www.amasci.com/ele-edu.html
http://www.ndted.org/EducationResources/HighSchool/Electricity/circuitdiagrams.htm
31
ACTIVITY 2: Behind The Plug: Circuits
and Ohm’s Law: Materials
32
Presentation:
Circuits
33
CIRCUIT PROBLEM SET
Use the appropriate equations to solve the following problems. Be sure to show all of you work.
Do not forget Sig Figs and unit!
SAMPLE PROBLEMS
Three resistors are connected in series. If placed in a circuit with a 12-volt power supply.
Determine the equivalent resistance, the total circuit current, and the voltage drop across and
current through each resistor.
Three resistors are connected in parallel. If placed in a circuit with a 12-volt power supply.
Determine the equivalent resistance, the total circuit current, and the voltage drop across and
current in each resistor.
34
1.




What kind of circuit is this?
What is the net resistance of this circuit?
What is the current drawn from the battery?
What is the power consumed by this circuit?
35
2.




What kind of circuit is this?
What is the net resistance of this circuit?
What is the current drawn from the battery?
What is the power consumed by the circuit?
http://www.csun.edu/~gsl05670/labs/circuits_ser_par.htm
http://www.glenbrook.k12.il.us/gbssci/phys/Class/circuits/u9l4d.html
36
CIRCUIT PROBLEM SET
RUBRIC
Use the appropriate equations to solve the following problems. Be sure to show all of you work.
Do not forget Sig Figs and unit!
SAMPLE PROBLEMS
Three resistors are connected in series. If placed in a circuit with a 12-volt power supply.
Determine the equivalent resistance, the total circuit current, and the voltage drop across and
current through each resistor.
R = 38ohms
I1 = .32A
I2 = .32 A
I3 = .32 A
Itotal = .32A
V1 = 3.5V
V2=2.24V
V3= 6.4V
37
Three resistors are connected in parallel. If placed in a circuit with a 12-volt power supply.
Determine the equivalent resistance, the total circuit current, and the voltage drop across and
current in each resistor.
R = 3.6ohm
I1=1.1A
I2=1.7A
I3=.6A
Itotal= 3.3A
V1=12V
V2=12V
V3=12V
1.




What kind of circuit is this?
series
What is the net resistance of this circuit? 1890ohm
What is the current drawn from the battery? .79 x 10-4 A
What is the power consumed by this circuit? .0012W
38
2.




What kind of circuit is this?
parallel
What is the net resistance of this circuit? 170 ohm
What is the current drawn from the battery?
.0088A
What is the power consumed by the circuit? .013W
39
OHM’S LAW/CIRCUIT LAB
PRE LAB ACTIVITY
1. Describe the proper placement of an ammeter in a circuit.
2. Describe the proper placement of voltmeter in a circuit.
3. Draw a circuit diagram that contains the following.
a. Two 1.5 volt batteries
b. One 22 ohm resistor
c. A voltmeter
d. An ammeter
4. Decode the following resistor
First band: yellow
Second band: blue
Third band: brown
Fourth band : silver
5. Draw a circuit diagram that contains the following
a. two 1.5 volt batteries
b. Three 22-ohm resistors in series
c. An ammeter
d. Three voltmeter
40
APPENDIX A
Rules for the Use of Meters
THE VOLTMETER
A voltmeter is used to determine the potential difference or voltage between two points in a
circuit. It is always connected in PARALLEL with the element to be measured. If you can
remove the voltmeters from the circuit without interrupting the circuit, you have connected
it correctly.
THE AMMETER
An ammeter is used to measure the current in a circuit and must always be connected in
SERIES. Since the internal resistance of an ammeter is very small, the meter will be
destroyed if it is connected in parallel. When you connect or disconnect the ammeter, the
circuit must be interrupted. If the ammeter can be included or removed without breaking
the circuit, it is incorrectly connected.
APPENDIX B
Resistor Color Code
How to read Resistor Color Codes
First the code
Black Brown Red Orange Yellow Green Blue Violet Gray White
0
1
2
3
4
5
6
41
7
8
9
How to read the code
First find the tolerance band, it will typically be gold ( 5%) and sometimes silver (10%).
The tolerance indicates the range of acceptable values for that resistor. For example, if
the resistor has a printed value of 100ohms and the tolerance is 5% - that resistor can
offer resistances 5% higher and 5% lower than 100 ohms
Starting from the other end, identify the first band - write down the number associated
with that color; in this case Blue is 6.
Now 'read' the next color, here it is red so write down a '2' next to the six. (you should
have '62' so far.)
Now read the third or 'multiplier' band and write down that number of zeros.
In this example it is two so we get '6200' or '6,200'. If the 'multiplier' band is Black (for
zero) don't write any zeros down.
If the 'multiplier' band is Gold move the decimal point one to the left. If the 'multiplier'
band is Silver move the decimal point two places to the left.
Resources: http://en.wikipedia.org/wiki/Circuit_diagram
http://www.glenbrook.k12.il.us/gbssci/phys/Class/circuits/u9l4a.html
Physics: Principles and Problems. Paul Zitzewitz and Craig Kramer
42
OHM’S LAW/CIRCUIT LAB
Purpose:

Use Ohm’s law to determine the values of resistors

Measure current and voltage to determine equivalent resistances in series and parallel
circuits
Concept and Skill Check
A circuit diagram (also known as an electrical diagram or electronic schematic) is a pictorial
representation of an electrical circuit. It shows the different components of the circuit as
simplified and standard pictograms, and the power and signal connections (buses) between the
devices.
CIRCUIT SYMBOLS
Example 1: SERIES
Description with Words: Three cells are placed in a battery pack to power a circuit containing
three light bulbs in series.
Example 2: PARALLEL
Description with Words: Three cells are placed in a battery pack to power a circuit containing
three light bulbs in parallel.
43
Materials
Circuit Board
Digital Multimeter
2 C batteries (1.5 volts)
various resistors
Procedure
PART A
1. Review Rules for Meters Use and Resistor Coding, located at the back of this lab packet,
before beginning the lab.
2. Obtain a resistor from your teacher. Decode the resistor. Record the resistance and
tolerance in Data Table 1
3. Set your circuit using the circuit board and one 1.5 volt battery. Use a blue wire to
connect one end of the resistor to the battery pack. All the other wires should be white
4. Carefully switch the multimeter to the DC voltage setting. Being sure to place the meter
in PARALLEL with the resistor, take a voltage reading across the resistor. Record this
value in Table 1.
5. Carefully switch the multimeter to the DC current setting. Remove the blue wire from
the circuit. Replace the blue wire with the multimeter probes. The ammeter is now
connected in series with the resistor. Record the value of the current through the resistor
in data table 1.
6. Repeat steps 1 through 5 using two 1.5 volt batteries. Record data in data table 1
7. Repeat steps 1- 6 for two different resistors
Observations and Data
DATA TABLE 1
Resistor
Printed
Tolerance Voltage
Value of
Range
(V)
Resistance
Current
(A)
R #1
R#1
R#2
R#2
R#3
R#3
44
Resistance
(Ohms)
Percent
Error %
ANALYSIS
1. Use data table 1 to calculate the resistance for each set of data, applying R=V/I. Show all
of your work. Record the resistances in data table 1.
2. Use the calculated resistances as actual values and the printed resistances as experimental
values. Determine the percent error for each trial. Show all your work and record your
values in data table 1.
3. If your percent error values are not within the tolerance range for the resistor, suggest
some reasons for the discrepancy.
4. State the relationship between the current flowing through a circuit and the voltage and
resistance of the circuit.
Procedure
PART B
1. Obtain three resistors from your teacher. Decode the resistors. Record these values in
data table 2.
2. Wire the circuit so that the three resistors are in series. Place a blue wire from one of the
battery terminals to one of the resistors. All other wires should be white.
3. Have your teacher check you circuit before you install the battery!!!
4. Once you circuit has been approved place one 1,5 volt battery in the battery pack.
5. Carefully witch the multimeter to the DC ammeter setting. Remove the blue wire from
the circuit. Replace the wire with the probes of the ammeter. The ammeter is now in
series with the resistors. Record the current reading in data table 2.
6. Remove the ammeter and replace the blue wire.
7. Carefully switch the multimeter to the DC voltage setting. Place the probes across each
individual resistor, then across all three resistors. You are placing the voltmeter in
parallel. Record these values in data table 2.
45
Observations and Data
DATA TABLE 2
Voltmeter Reading (V)
R#1 R#2
R#2 Ammeter
reading (A)
V#1
V#2
V#3
V total
Tolerance
Analysis
5. Use the values for current and total voltage in data table 2 to calculate equivalent
resistance. This is the actual value of your equivalent resistance. Using the printed
values of your resistances determine your experimental value of the equivalent resistance.
Perform a percent error. Show all of you work.
6. Use your data in table 2 to describe how the voltage drops across individual resistances
are related to the total voltage drop in a series circuit.
46
Procedure
1. Obtain a set parallel circuit from your teacher. DO not rewire anything on the circuit
board.
2. Decode the three resistors on the board. Record these values in data table 3.
3. Carefully switch the multimeter to the DC ammeter setting. Remove the blue wire from
the battery pack to the first resistor. Replace the wire with the probes of the ammeter.
The ammeter is now wired in series with the first resistor. Record the value of this
current in data table 3.
4. Replace the blue wire.
5. Remove the blue wire that runs from the first resistor to the second resistor. Replace this
wire with the probes of the multimeter. You are now wired in series with the second
resistor. Record the value of this current in data table 3
6. Replace the blue wire
7. Remove the blue wire that runs from the second to the third resistor. Replace this wire
with the probes o the ammeter. You are now wired in series with the third resistor.
Record the value of this current in data table 3.
8. Replace the blue wire.
9. Remove the red wire that runs from the battery pack to the first resistor. Replace the red
wire with the probes of the ammeter. You are now wired in series with the circuit.
Record the value of this value, the total current, in data table 3.
10. Replace the red wire.
11. Carefully switch the multimeter to the DC voltage setting. Place the probes of the meter
across the first resistor. Record the value of this voltage in table 3.
12. Place the probes across the second resistor. Record this value in table 3.
13. Place the probes across the third resistor. Record this value in table 3
14. Place the probes across all three resistors. Record this value in table 3.
Observations and Data
Data Table 3
R#1
R#2
R#3
Ammeter Reading (A)
I
I#1
I#2
Voltmeter Reading (V)
I#3
Tolerance
47
V
V#1
V#2
V#3
Analysis
7. Draw a circuit diagram for the circuit that you analyzed in Part C of the lab. Include the
two batteries, three resistors, ammeters, and voltmeters.
8. Use the readings from Table 3 to calculate the following
a. The measured equivalent resistance, where R=V/I
b. The measured current, I=I#1+I#2+I#3
c. The measured resistance of R#1, where, R#1=V#1/I#1
d. The measured resistance of R#2, where R#2=V#2/I#2
e. The measured resistance of R#3, where R#3= V#3/I#3
f. The calculated equivalent resistance, where R = 1/R#1+1/R#2+!/R#3
48
9. a. Compare the measured value of I to the sum of I#1+I#2+I#3.
b. Compared the calculated equivalent resistance(answer 8F) to the measured equivalent
resistance(answer 8A). Use the measured resistance as your actual and the calculated as
your experimental. Perform percent error. Was the error within the tolerance range of
the resistors?
10. How does the current in the branches of a parallel circuit relate to the total current in the
circuit?
11. How does the voltage drop across each branch of a parallel circuit relate to the voltage
drop across the entire circuit?
12. As more resistors are added in parallel to an existing circuit, what happens to the total
circuit current?
49
EXTENSION
1. Obtain the extension circuit from your teacher. DO not change any of the wiring.
a. Draw a circuit diagram
b. Is this a series or a parallel circuit?
c. Calculate the total resistance of this circuit.
2. Place a compass next to the circuit. What happens to the needle? Make a hypothesis
based on your observations.
Application
1. A set of miniature decorative tree lights contains 50 individual bulbs of equal resistance,
wired in series, and is designed for 120 v operation. If the set uses 1.0 A of current, what
is the resistance of an individual light bulb and what is the voltage drop across each light
bulb?
2. What type of wiring exists within you home and the power grid? Why is this beneficial?
3. Below is a one line diagram of a Distribution Network. The circuit diagram below is a
representation of the same network. Use both diagrams to answer the question below.
50
Equivalent Transmission and Generation Grid
AC
VOLTAGE
138,000V
STEP DOWN
TRANSFORMER
4160 V
Distribution Grid
CIRCUIT
BREAKER
STEP DOWN
TRANSFORMER
240V
10-2 ohms
10-2 ohms
10 ohms
10 ohms
Arrows represent Houses
10-2 ohms
10 ohms
12 V
a. Where would a fault have to occur on the diagrams below to disrupt power to the MOST
consumers? Place a letter A at this point on the diagrams.
b. Where would a fault have to occur on the diagrams below the disrupt power to the
LEAST amount of consumers? Place a letter B at this pint on the diagrams
51
ACTIVITY #3 OHM’S LAB/CIRCUIT
LAB
52
Teacher’s Notes
Objective: Students explore the relationships between voltage, current, and resistance and
investigate the important distinctions between series and parallel circuits in a hand on laboratory
experience..
Time Requirement: Two 48 minute class periods
Materials Needed * Ohm’s Law/Circuit Lab (1 for each student)
 Circuit boards
 Blue and white conductive wire
 Digital multimeters
 Various resistors
 Batteries (D batteries)
 compass
Class Activities







Prior to the start of class, the teacher should organize the lab materials.
Students will be working in groups of two. Each lab group should have
one multimeter, one circuit board, and two C batteries. The teacher
should keep the resistors at the front of the room.
Class will begin with the teacher walking around the room to make sure
that all of the students have completed the pre-lab activity
Students will be asked to share the answers of their prelab activity on
the board. Students will be encouraged to correct any mistakes they
may have made on this activity. The teacher should be careful to clarify
any confusion in meter attachment, circuit diagrams, and resistor
decoding.
The teacher should ask if the students are clear on the procedures for the
day. Clarifications should be made if necessary. In particular, the
teacher should be careful to explain the placement of the blue wire in
the circuit The blue wire is meant to help students understand ammeter
placement in a circuit. The ammeter will always replace a blue wire,
thus minimizing the possibility of incorrect ammeter placement
Students should be organized into groups of two. Each group should
receive a lab box consisting of two c batteries, a multimeter, and a
circuit board.
Students should come up to the teacher to receive a resistor.
Once the students have correctly decoded the resistor they should notify
the teacher, who should sign off of their lab and once again check to
make sure the students understand how to attach an ammeter and
voltmeter.
53


Students can work independently to finish PART A of the lab. They
should answer question 1-4 when they are finished. Students who do
not finish this in class will be expected to complete it for homework
THIS MAY BE A GOOD POINT TO BREAK FOR DAY ONE
DAY 2






ASSESMENT



Prior to the start of class, the teacher should organize lab materials into
lab boxes. Each box should contain a circuit board, three different
resistors, and a digital mutlimeter. The teacher should keep the
batteries at the front of the classroom. Furthermore, the teacher will
need to prepare between 6 and 8 parallel circuits. Each circuit should
have three different resistors wired in parallel. The teacher will need to
make sure that the wiring is such that blue wires are used in places
where ammeters can be substitutes. Also a few combo circuits should
be set up for the extension portion of the lab. Students will be asked to
look at this circuit and draw the corresponding diagram for it.
Students should begin Part B of the lab. Once they have correctly
decoded their resistors they should call over their teacher. If they are
correct, the teacher will sign off on he lab and give the students their
batteries. Once again the teacher should make sure the students are
aware of meter placement.
When students have finished Part B of the Lab they should answer
question 5 and 6.
Students are to then begin Part C. By this point they should understand
that blue wire should be pulled for ammeter placement, however the
teacher should closely monitor their progress.
After completing Part C students should complete the remaining
analysis and application questions.
NOTE: Application question 3 is difficult. It asks the students to
correlate a one line diagram and circuit diagram. This question leads
into the next activity on safety and circuit breakers
Pre Lab Activity
Ohm’s Law/Circuit Lab Analysis and Application Questions
Teacher’s qualitative assessment of student’s ability to work in groups
to complete a lab
54
ACTIVITY 4: DISTRIBUTION
GRID
55
Teacher’s Notes
Objective: Students will expand their knowledge of circuit breakers, current leakage, and
electrocution hazards. They will also integrate their knowledge or circuit diagrams, one line
diagrams, and ohm’s law with how the distribution network operates.
Time Requirement: 48 minutes
Materials Needed: - Student Electrical Safety worksheets (1 for each student)
- Safety PowerPoint
Class Activities
 Class will begin with the teacher asking if there are any final questions from the students
regarding the lab. Students will most likely have questions regarding Application #3.
Remind the students that this question will not be graded for accuracy on the lab; its
purpose was to start the students thinking about how circuits and distribution grids are
related. The teacher will answer any questions that arise and then collect the Ohm’s Law
Circuit Lab.( 3- 5 minutes )


The teacher will then present the power point on Safety. The first few slides correspond
with Application question #3 on the lab. Ask the students to share their answers to
application question 3 with the rest of the class. After listening to student answers, the
teacher should explain to the students that in reality there are multiple places on the
diagram where a fault could occur to disrupt the service to the most consumers. This is
due to a circuit breaker on the network that trips when a certain current consumption is
reached. Make sure students understand how a reduction in resistance due to a fault
increases current. Continue with the rest of the safety PowerPoint.(25 minutes)
The teacher will hand out 5 student problems. Students are to work on these together until
the end of class. Each student will be expected to turn in their own copy of this
tomorrow. ) 15 - 20 minutes)
Assessment:

Problem set
Resources
 http://en.wikipedia.org/wiki/Resistivity
 http://hyperphysics.phy-astr.gsu.edu/hbase/electric/shock.html
 http://www.allaboutcircuits.coml
 http://www.puco.ohio.gov/PUCO/Consumer/information.cfm?doc_id=1262
 http://static.howstuffworks.com/gif/circuit-breaker-intro.jpg
56
ACTIVITY 4: DISTRIBUTION
GRID: MATERIALS
57
Presentation:
Circuits and Safety
58
ELECTRICAL SAFETY WORKSHEET
1. What is the resistance of a superconductor if 300.0 milliamps of current are passing
through the sample and 4.2 millivolts are measured across the voltage probes?
2. What is the resistivity of the rectangular sample in problem #1, if the material is 2.5 mm
wide, 3.4 mm high and the distance between the probes is 2.5 cm?
3. Imagine connecting rectangular samples of copper and silver as in problem #3. Typical
resistivities of these materials are 1.8 x 10-8 ohm-meters and 1.6 x 10 -8 ohm-meters,
respectively. What resistances will be measured?
4. Household circuits are often wired with two different widths of wires: 12-gauge and 14gauge. The 12-gauge wire has a diameter of 1/12 inch while the 14-gauge wire has a
diameter of 1/14 inch. Thus, 12-gauge wire has a wider cross section than 14-gauge wire.
A 20-Amp circuit used for wall receptacles should be wired using 12-gauge wire and a
15-Amp circuit used for lighting and fan circuits should be wired using 14-gauge wire.
Explain the physics behind such an electrical code.
59
5. Explain the risk involved in using 12-gauge wire in a circuit that will be used to power a
14-ampere power tool.
6.
Determine the resistance of a 1 mile length of 12-gauge copper wire. Given: 1 mile =
1609 meters and diameter = 0.2117 cm.( Copper 1.7 x 10-8 )
7. Why is more dangerous to touch an outlet when your hands are wet than when your
hands are dry. Explain your answer in terms of voltage, current, and resistance.
8. If the resistance of a circuit is tripled, what happens to the current? What happens to the
voltage?
60
ELECTRICAL SAFETY WORKSHEET
RUBRIC
1. What is the resistance of a superconductor if 300.0 milliamps of current are passing
through the sample and 4.2 millivolts are measured across the voltage probes?
V=IR .014ohm
2. What is the resistivity of the rectangular sample in problem #1, if the material is 2.5 mm
wide, 3.4 mm high and the distance between the probes is 2.5 cm?
P=RA/l
4.8 x 10-6 ohm meter
3. Imagine connecting rectangular samples of copper and silver as in problem #3. Typical
resistivities of these materials are 1.8 x 10-8 ohm-meters and 1.6 x 10 -8 ohm-meters,
respectively. What resistances will be measured?
P=RA/l
Cu = 5.3 x 10 -5 ohm
Ag = 4.7 x 10-5 ohm
4. Household circuits are often wired with two different widths of wires: 12-gauge and 14gauge. The 12-gauge wire has a diameter of 1/12 inch while the 14-gauge wire has a
diameter of 1/14 inch. Thus, 12-gauge wire has a wider cross section than 14-gauge wire.
A 20-Amp circuit used for wall receptacles should be wired using 12-gauge wire and a
15-Amp circuit used for lighting and fan circuits should be wired using 14-gauge wire.
Explain the physics behind such an electrical code.
12 gauge wire has more area so it has less resistance; therefore it can carry more current
61
5. Explain the risk involved in using 12-gauge wire in a circuit that will be used to power a
14-ampere power tool.
Too much current can cause a fire hazard
6.
Determine the resistance of a 1 mile length of 12-gauge copper wire. Given: 1 mile =
1609 meters and diameter = 0.2117 cm.( Copper 1.7 x 10-8 )
P=RA/l
1.575 x 10 -16 ohm
7. Why is more dangerous to touch an outlet when your hands are wet than when your
hands are dry. Explain your answer in terms of voltage, current, and resistance.
When you touch the outlet you provide a ground (a path to zero potential) therefore a voltage is
applied across you.
Wet hands have less resistance so more current will flow
8. If the resistance of a circuit is tripled, what happens to the current? What happens to the
voltage?
The current is reduced by 1/3, voltage is not altered
62
ACTIVITY 5: Power Plant
63
Teacher’s Notes
Objective: Students gain an understanding of how a power plant operates. They will be
introduced to the idea of magnets and magnetic fields. Furthermore, students will
experimentally determine factors that influence induced current.
Time Requirement: 48 minutes
Materials Needed: - Electromagnetic Induction Lab (1 for each student)
- Power Plant PowerPoint
Class Activities
 The Teacher will ask if there are any questions on the Safety worksheet and then collect
the worksheet.
 The teacher will present the Power Plant Power Point Presentation. The second slide in
the presentation contains a hyperlink to the site
http://www.tampaelectric.com/Education/TEEDElecgen.html This site steps the students
though the different stages of the generator. ( 10 minutes)

The teacher will then hand out a copy of the Electromagnetic Induction Lab to every
student. Students will complete the lab in lab groups. Thins activity is meant to address
the inquiry goal of the module. Students will be given a problem and the solution of the
lab. They will in turn be asked to develop a procedure to unite the two. The teacher
should explain that this is how engineers actual work in the real world. Students should
be encouraged to answer every Observation and Data and Analysis question on the
laboratory. They may have some frustration, since the equations for this chapter will not
have been presented at this point. Tell them to analyze their data carefully and make
their best guesses at answers. (30- 40 minutes)
Assessment:
 Electromagnetic Induction Lab
Resources
“Physics Principles and Problems” Glencoe 1992
http://www.scienceproject.com/
http://science.howstuffworks.com
gcsescience.com
http://www.tampaelectric.com/Education/TEEDElecgen.html
64
ACTIVITY 5: POWER PLANT:
MATERIALS
65
Presentation:
Inside the Power Plant
66
ELECTROMAGNETIC INDUCTION LAB
PURPOSE: Create a procedure to determine the following.
1. The number of coils in an electromagnetic is directly proportional to the magnitude of
induced current
2. The strength of the magnetic field is directly proportional to the magnitude of the induced
current.
3. The velocity of the moving magnet is directly proportional to the magnitude of the
induced current.
MATERIALS
Galvanometer with zero in center of scale
1-coil turn or wire
25- turn coil of wire
100-turn coil of wire
2 bar magnets
connecting wires
PROCEDURE
67
OBSERVATIONS AND DATA
68
ANALYSIS
1. Summarize the factors that affect the amount of current and EMF induced by a magnetic
field.
2. In your textbook, the equation given for electromotive force induced in a wire by a
magnetic field is EMF = Blv, where B is the magnetic induction, l is the length of the
wire in the magnetic field, and v is the velocity of the wire with respect to the field.
Explain how the results of your experiment substantiate this equation.
3. What happens when a conducting wire is held stationary in or is moved parallel to a
magnetic field. Explain.
EXTENSION
1. Is there another way in which the magnet and the wire can interact, besides the magnet
moving in and out of the coils of wire, so that the galvanometer moves?
69
ELECTROMAGNETIC INDUCTION LAB
RUBRIC
Student’s procedures will vary. As long as the procedures are detailed and
successfully test the three variables students should receive credit.
ANALYSIS
4. Summarize the factors that affect the amount of current and EMF induced by a magnetic
field.
Number of coils, velocity at which magnet is pushed into wire, strength of magnets
5. In your textbook, the equation given for electromotive force induced in a wire by a
magnetic field is EMF = Blv, where B is the magnetic induction, l is the length of the
wire in the magnetic field, and v is the velocity of the wire with respect to the field.
Explain how the results of your experiment substantiate this equation.
Students should summarize their observations and explain how it validates the above equation
6. What happens when a conducting wire is held stationary in or is moved parallel to a
magnetic field? Explain.
The galvanometer does not move
70
ACTIVITY 6: INSIDE THE GENERATOR:
Electromagnetism
71
Teacher’s Notes
Objective: Students will gain knowledge of electromagnetic induction. They will be exposed to
the equations for magnetic field, magnetic force, and induced emf.
Time Requirement: 48 minutes
Materials Needed: - Electromagnetism Power Point
-Electromagnetic Induction Lab
Electromagnetism Worksheet(1 for each student)
Class Activities
 Students may require some additional time to tidy up their procedures from the previous
day’s lab(10 minutes)
 The teacher will ask students to share their procedures, observations and analysis answers
from the Electromagnetic Induction Lab with the class. . Students should be aware of the
factors that are directly related to the strength of the resulting induced current (1) the
number of turns in a coil or a coil’s length (2) The strength of a magnet varies and (3)
The speed at which the magnet enters and leaves the coils of wire. Students should also
be aware that a stationary magnet will not produce an induced current because a changing
magnetic field is required for an induced current. Students will then turn in their labs (10minutes)
 The teacher will then present the Electromagnetism PowerPoint. Students should take
notes and write down the equations. Be sure students understand the solved examples. (
20 minutes)
 Students will then complete 5 questions Electromagnetism worksheet. What students do
not finish will be homework (5-8 minutes)
Assessment
 Electromagnetic Induction Lab
 Electromagnetism Worksheet
Resources
Physics Principles and Problems” Glencoe 1992
gcsescience.com
“Physics” Douglas GIancoli.Prentice Hall 1991
http://solar-center.stanford.edu/magnetism/magneticforce.html
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magfor.html
http://www.school-for-champions.com/science/magnetism_lorentz.htm
http://www.sunblock99.org.uk/sb99/people/DMackay/ac.html
http://Howstuffworks.com
http://bigvalleynews.net/BigValleyPower/TourOfBigValleyPowerLLC.html
http://avstop.com/AC/apgeneral/TRANSFORMERS.html
http://www.ibiblio.org/kuphaldt/electricCircuits/AC/AC_9.html
http://dept.physics.upenn.edu/courses/gladney/phys151/lectures/lecture_mar_21_2003.shtml
kilby.sac.on.ca/physics/sph3u/1-EM
72
ACTIVITY 6: INSIDE THE GENERATOR:
Materials
73
Presentation:
Electromagnetism
74
ELECTROMAGNETISM WORKSHEET
1. Describe the two different right hand rules. Use your own words. You may use diagrams
in your explanation
2. How much current is flowing in a wire 3.00m long if the force on it is 0.900N when
placed in a uniform 0.0800 Tesla field?
3. The force on a wire carrying 30.0A is a maximum of 3.80N when placed between the
pole faces of a magnet. If the pole faces are 25.0 cm in diameter, what is the strength of
the magnetic field?
4. An electron experiences the greatest force as it travels 3.5 x 105 m/s in a magnetic field
when it is moving southward. The force is upward and of magnitude 6.8 x 10-13 N. What
is the magnitude and direction of the magnetic field? .
75
5. A uniform magnetic field B, with magnitude B = 1.2 x 10-3 T, points vertically upward
throughout the volume of a laboratory chamber. A proton with a velocity v = 3.2 x 107
m/s enters the laboratory moving horizontally from south to north. Find (a) the magnitude
and (b) the direction of magnetic force on the proton.
6. Am emf of 0.45V is induced ina straight conductor having a length of 20.0cm. The
magnetic field is moving at 600.0 cm/s with repect ot he conductor. What is the value of
the magnetic field?
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ELECTROMAGNETISM WORKSHEET
RUBRIC
1. Describe the two different right hand rules. Use your own words. You may use diagrams
in your explanation
#1 point right hand thumb in direction of current, fingers wrap in direction of field
#2 point right thumb in direction of current, first finger in direction of field, stick out second
finger – it points in direction of force
2. How much current is flowing in a wire 3.00m long if the force on it is 0.900N when
placed in a uniform 0.0800 Tesla field?
B=F/Il
3.75A
3. The force on a wire carrying 30.0A is a maximum of 3.80N when placed between the
pole faces of a magnet. If the pole faces are 25.0 cm in diameter, what is the strength of
the magnetic field?
B=F/Il .507 T
4. An electron experiences the greatest force as it travels 3.5 x 105 m/s in a magnetic field
when it is moving southward. The force is upward and of magnitude 6.8 x 10-13 N. What
is the magnitude and direction of the magnetic field?
F=qvB
12T
5. A uniform magnetic field B, with magnitude B = 1.2 x 10-3 T, points vertically upward
throughout the volume of a laboratory chamber. A proton with a velocity v = 3.2 x 107
m/s enters the laboratory moving horizontally from south to north. Find (a) the magnitude
and (b) the direction of magnetic force on the proton.
F=qvB 6.1 x 10 -15 N
out of page
7. Am emf of 0.45V is induced ina straight conductor having a length of 20.0cm. The
magnetic field is moving at 600.0 cm/s with repect ot he conductor. What is the value of
the magnetic field?
Emf=BLv
0.45V=B(.200m)(6.00m/s)
B = .38T
77
ACTIVITY 7: THE GENERATOR
78
Teacher’s Notes
Objective: Students will gain hands on knowledge of how an electric generator functions.
Students will work in teams to build a simple generator and answer questions regarding the
process.
Time Requirement: Two to three 48 minute class sessions
Materials Needed: - Computer with Internet access
Simple Generator Lab (per student)
- Ceramic Magnets, 1cmx2cmx5cm Radioshack #64-1877
-
(each group will require 4 of these )
-
#30 magnet wire 200ft, Radio shack #278-1345
-
( each group will require enough for 300 turns)
-
Cardboard strip, 8cmx 30 cm – 1 per group
-
Use William Beaty’s instructions on how to construct cardboard towers
Large nail, 8 cm long ( one per group)
Mini Incandescent lamp, 1.5 V 25mA RAdioShack #272-1139 ( one
per group)* Note you must use this low voltage bulb for best results
-
Tape
Multimeter(one per group)
Ultra-simple Electric Generator Instructions ( © 1996 William Beaty)
located at http://amasci.com/amateur/coilgen.html
-
This should be used as a teacher resource only
Class Activities
 The teacher will ask students if there are any questions regarding the previous night’s
homework worksheet. Once questions are answered, the teacher will collect the
assignment.
 The teacher will then hand out the Electric Generator Lab. The teacher will assign
students into lab groups of four. The teacher will then go through the directions with the
students. The students will have to design a cost effective and efficient electric generator.
A materials list and a price sheet are provided in the student packet. Students must keep
track of how much they spend. The group who is able to develop a working generator
with the lowest budget will win. The first part of the lab is step up according to
engineering design process. Each step of this process is highlighted and underlined.
 Students will then be encouraged to use the internet to develop a design for an electric
generator. Some students may not need to use the internet, depending on their level of
knowledge. All design procedures and materials must be approved by the teacher. If
students get stuck, encouraged them to Google terms like electric generator. The teacher
should ask the students to write down a preliminary materials list at the end of ten
minutes. IF the students have not recognized the need for the magnet wire and magnets
at this point, help them find appropriate websites. A great site for the construction of a
simple generator is http://amasci.com Also, if you answer questions during this 10
minute check-up, be sure to charge the students. You will notice that internet usage
according to the consultant fees is free only for the first twenty minutes. Teachers should
have the students begin their materials and procedures after twenty minutes. Most of the
designs online will lead students to the same required materials, which are listed above.
Teachers should consult William Beaty’s instructions on generator construction (located
at the above website) in order to obtain the correct materials and to familiarize
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themselves with potential downfalls in design and material selection. The materials in
Beaty’s lab are all available at RadioShack. I recommend constructing the card board
tubes ahead of time, in order to save time Have students explain their hypotheses and
theories when you are approving their materials and procedures. If students material
requests are for objects not listed above, try to obtain these materials for students (as long
as they are reasonable) The addition of these materials may make their generators
inadequate, but they will have an opportunity for a redesign. This will of course cost
them more money.
Once students have an approved material list and procedure they can move on to part 2 of
the lab. Students will create their generators, test voltage and current, and calculate
power of their design. They will also have to have their budget page signed by the teacher
THIS IS A GOOD PLACE TO STOP FOR DAY ONE
DAY 2
Students may require a portion of this day to complete their initial designs
When all of the students have working designs and their budgets have been submitted to
the teacher, will then ask students to share their power calculations for their generators.
Students will be asked to hypothesize how they can alter their design to make it more
powerful. They will complete the three hypotheses listed on page three of the lab.
Students who have knowledge of electromagnetism (Electromagnetism Lecture of
module and Electromagnetism worksheet) should be able to reference the equation E =
Blv to determine the three variables that effect the generation of an induced emf and
current. . Students who have not gone through this lecture will need more guidance (1015 minutes)
Based on these hypotheses, students should develop a procedure and data table for their
experiments Students will follow the lab procedure to obtain data. They will also be
asked to create three graphs demonstrating the results of their experiments. and answer
two lab questions.(35-40minutes)
The student design should be evaluated using the constraints and criteria listed under the
problem statement. Only those designs which generate 2 Watts of power can be
considered. Two ratios must be calculated for every design that meets the constraints.
First a ratio of capitol cost (cost of original generator) versus power (which in this case is
2watts). SO for instance if a groups total cost of design was $1000, their ratio would be
500($1000/2watts) The second ratio that n=must be determined is capitol cost versus
maximum power. The students will take the cost of their most powerful generator (in
some cases this cost may be the same as their original cost) and they will divide it by
maximum power. For example, if the group above spent$1000 on their generator and
was able to generate 4Watts, their new ratio would be 250($1000/4watts) Finally these
two ratios should be added together to get a final number. In this sample case the number
would be 750 (500 + 250). The group with the lowest number wins the design
competition.
Students may or may not have time to complete the extension of the lab. This activity
can be saved for a third day of lab if necessary. In the extension students will experiment
with turning the nail when the bulb is connected to the generator and when it is
disconnected. They should detect a higher level of difficulty in turning the nail when the
bulb is connected. Ask them to hypothesize why this is occurring. Once all students
have generated hypotheses, ask the students to share their conclusions. Through this
80
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discussion they should arrive at the idea, with the teacher’s aid, that when the bulb is
connected it resists the flow of current. This resistance can be felt when they turn the
nail.
If the teacher wishes, there is an extra activity for this lab that explores the differences
between the engineering design process and the scientific method. The presentation can
be used to generate student discussion. Ask the students whether the lab was an
engineering problem or a science problem.
Collect labs once students have completed their analysis
ASSESSMENT
 Teacher’s qualitative assessment of student participation in design process and class
discussion
 Electric Generator Lab
RESOURCES
http://www.thesolutionsite.com/lesson/26112/Unit_1_student_lesson_1.html
http://www.thesolutionsite.com/lesson/26112/unit%201%20Lab__building_a_generatorday%201&%202.html
http://amasci.com/amateur/coilgen.html
81
ACTIVITY 7: THE GENERATOR:
Materials
82
ELECTRIC GENERATOR
STEP ONE: Engineering Design
Problem: You must develop a cost efficient process to light up a light bulb
Constraints and Criteria
1. Your generator must produce 2Watts of power to be considered in the design contest
2. Designs will be evaluated based on capitol costs of production at 2 watts
3. Design will be evaluated on capitol costs at maximum power
4. The ratios in criteria #2 and #3 will be added together to get an overall score. The group
with the lowest score will win the design contest.
Research and Investigation
Your first task is to search the Internet for materials and procedures on how to build a generator
and produce enough electricity to light a 4 Watt light bulb in a lab situation. You must select
materials from a materials list and create a lab procedure for building the electric generator. You
will notice that every material has a price. You must keep track on the materials you use on your
budget sheet. Furthermore, information also has a price. In the real world when engineers are
designing, they must pay consultants a fee in order to have questions answered and ideas
clarified. At the bottom of the materials list is a list of consultants’ fees. You must keep track of
these fees on your budget sheet. Use the lab report below to organize your information. Lastly,
be sure to cite the websites that you used as references in the resource portion of the lab
Alternative Solutions
You must generate at least one, preferably two, alternative solutions for your problem statement.
You should list the materials and procedures for these alternative solutions in the appropriate
space in the lab report. Be sure to list materials prices and record websites used as reference.
Optimal Solution
Once you have generated two or three possible solutions, you must evaluate them and decide
upon the most cost efficient and effective design. Consider the constraints and criteria for you
project when evaluating your solutions. Decide upon a design solution as a group and write
down a detailed list of required materials and corresponding prices, and a procedure for
construction. Submit these completed items to your teacher.
Construction
Based on your optimal solution create your generator from your materials. BE sure to keep track
of materials costs and consultation fees on your budget report.
83
Analysis and Testing
It is time to test your design and obtain data. Use the Design, Analysis, and Testing Lab Sheet to
get data from your generator.
Final Evaluation
Each team’s design will be evaluated using the constraints and criteria listed under the problem
statement portion of the lab.
84
ELECTRIC GENERATOR
Solution #1
Materials
Cost
Procedure
Resources
Solution #2
Materials
Cost
Procedure
Resources
85
Solution #3
Materials
Cost
Procedure
Resources
86
ELECTRIC GENERATOR
OPTIMAL SOLUTION
Materials
Cost
PROCEDURE
Resources
87
ELECTRIC GENERATOR
STEP TWO: DESIGN, ANALYSIS AND TESTING
Once your research is complete and your teacher has approved your materials, procedure, and
budget sheet your lab group can start enacting your procedure. Once you have constructed your
generator, follow the procedure below to obtain data.
Part 1: Creation of the generator
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


Build your generator
Connect the generator to the bulb
Using the multimeter, obtain voltage and current readings (If you do not obtain voltage or
current readings, something may be wrong with your design. It is time to reassess the
construction and look for possible faults. See Redesign portion below)
Record your meter readings in the table below
Using the power equation below, determine the power of your device
P (power in watts) = I (current in amperes) x V (voltage in volts)

Fill in the table below
Current (amps - A)
Voltage (volts - V) Power (Watts - W)
original setup
Redesign:
If your generator does not produce a voltage or current you will have to redesign your generator.
This may require additional research on the computer. List your new set of materials and
modified construction procedure below. Be sure to add theses additions to your budget sheet.
88
ELECTRIC GENERATOR
PROBLEM#2: Can your generator produce more power?
Your generator may not have been powerful enough to light the bulb, but as long as a voltage
and a current reading were obtained, you may still have some hope. What changes can you make
to your original design to make the generator more powerful? I will give you a hint; there are
three major modifications all lab groups can make to increase the power of their generators. Fill
in the hypotheses below.
Hypothesis#1
If the number of coils ________________ the induced current
will_______________________.
Hypothesis #2
If the number of magnets _______________ the induced current
will__________________.
Hypothesis #3
If the velocity of turning ____________________ the induced
current will_____________________.
We will evaluate all of the designs in a second round once the following
modifications have been made to the designs.
89
ELECTRIC GENERATOR
Part 2: Making the generator more powerful
Design a procedure to test your three hypotheses. List this procedure below.
PROCEDURE
90
Create a data table to organize your experimental data. Fill in the variable that you tested in the
right hand column.
Variable
Current (amps - A)
Voltage (volts - V) Power (Watts - W)
Analysis
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Produce a bar graph of the amount of motion on the production of Power.
Create a line graph demonstrating the effect the number of coils has on Power
Create a line graph showing the effect that the number of magnets has on the Power.
Questions:
1. How is electric current generated?
2, Which variable had the greatest effect on the power produced?
91
3. What modifications would you make to your original design if you were faced with this task
again?
Extension:
Disconnect one wire from the light bulb. Spin the magnet. While spinning the magnet, have
one lab partner touch the wires together so that the bulb lights up gain. Is the nail still easy to
spin? Keep spinning the magnet while you lab partner connects and disconnects the bulb.
Feel any differences in how hard you must turn the nail? Also try spinning the magnets
while your friend connects the generator wires directly together (with no bulb connection).
Hypothesize the reason it is more difficult to turn the nail when the bulb is connected.
.
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MATERIALS LIST
Ceramic magnet --------------------------------------- $5,000
Toothpick -----------------------------------------------$500
Nail ------------------------------------------------------$750
Screw ---------------------------------------------------$650
String --------------------------------------------------- $ 1000
Wire ---------------------------------------------------- $1500
Cardboard --------------------------------------------- $2500
Resistor ------------------------------------------------ $500
Plastic Washer ---------------------------------------- $70
Tape ------------------------------------------------- $100 a piece
CONSULTANT FEE
Computer research -----------------First 20 minutes free
Every minute after this $1000
Teacher ------------ ----------1st question - ------$100
2nd question -------$500
every question thereafter $2500
Students--- you may ask other lab groups for advice. If you do
this it will cost you $2500. The money you pay them will go
into their budget.
93
BUDGET
Materials – List all of your materials and their corresponding prices
Material
Price
TOTAL
94
CONSULTANTS – List all of your consultants’ fees
Consultant
Fee
TOTAL
WAGES – List any fees that you obtained through consultant
Group you helped
Fee you obtained
TOTAL
COST OF PROJECT – Add up you costs and subtract your wages.
MATERIALS TOTAL
CONSULTANT FEES
WAGES(subtract theses from the other two)
TOTAL COST OF PROJECT
95
Presentation:
Engineering and Science
96
DAY 11
ACTIVITY 8: Generators and
Transformers
97
Teacher’s Notes
Objective: Students will gain knowledge of how induced current works in generators and
transformers. They will also gain insight into why AC voltage is produced by generators and
why it is necessary work the functioning of transformers
Time Requirement: 48 minutes
Materials Needed: - Generator and Transformer Power Point
-Generator and Transformer worksheet (1 for each student)
Class Activities
 The teacher will present the Generator and Transformer Power point. The teacher should
be sure to further elaborate how induced current works inside the generator. Also,
students should understand the basic idea behind a transformer. The teacher should
explain that a changing magnetic field appears in the iron core due to the alternating
current in the primary coil. This magnetic field is transmitted through the core to the
secondary coil where it induces a current. An alternating current is required since direct
current will not produced a changing magnetic field – therefore no induced current can
occur. (20 minutes)
 Teacher will distribute Generator and Transformer Worksheet to students and have them
complete these worksheets in lab groups of 4. If students complete this worksheet within
this time frame they can turn it in, otherwise the worksheets homework.(28 minutes)
Assessment
 Generator and Transformer Worksheet
Resources
http://avstop.com/AC/apgeneral/TRANSFORMERS.html
http://bigvalleynews.net/BigValleyPower/TourOfBigValleyPowerLLC.html
http://science.howstuffworks.com/power3.htm
http://www.sunblock99.org.uk/sb99/people/DMackay/ac.html
http://www.ibiblio.org/kuphaldt/electricCircuits/AC/AC_9.html
98
ACTIVITY 8: Generator and Transformer:
Materials
99
Presentation:
Generators and Transformers
100
GENERATOR AND TRANSFORMER WORKSHEET
1. Describe in your own words how a generator creates electrical energy.
2.
What is the basic function of an electric generator?
3. What are the benefits of AC voltage?
4. What is a step up and a step down transformer? How do they work? Where are they
located?
5. Draw a diagram showing the different parts of the power grid. Be as specific as you
an. Trace the flow of current from the generator to the outlet
101
6. The device shown below is an iron core transformer. It is used to change AC voltage,
by either stepping the voltage up or down. It utilizes two conductive coils and an iron
core. Explain how this device can (1) induce a current in the secondary coil (2) have
that current be higher or lower in value.
7. Why do transformers require AC voltage to operate?
102
GENERATOR AND TRANSFORMER WORKSHEET
RUBRIC
1. Describe in your own words how a generator creates electrical energy.
A turning magnetic induces a current in a conductor
2.
What is the basic function of an electric generator?
Conversion of mechanical into electrical energy
3. What are the benefits of AC voltage?
Long distance transmission, ability to utilize transformers
4. What is a step up and a step down transformer? How do they work? Where are they
located?
Step up changes lower voltages to higher voltages – these are located outside of the
power plants
Step down changes higher voltages to lower voltages – these are located at substations
and on the distribution grid
An alternating voltage is applied over one coil, which in turn induces a voltage in the
other coil
5. Draw a diagram showing the different parts of the power grid. Be as specific as you
an. Trace the flow of current from the generator to the outlet
Diagrams will vary
103
6. The device shown below is an iron core transformer. It is used to change AC voltage,
by either stepping the voltage up or down. It utilizes two conductive coils and an iron
core. Explain how this device can (1) induce a current in the secondary coil (2) have
that current be higher or lower in value.
An alternating voltage is applied over one coil, which in turn induces a voltage in the
other coil
The turn ratio will determine whether a higher or lower voltage is induced in the second coil
7. Why do transformers require AC voltage to operate?
a changing magnetic field appears in the iron core due to the alternating current in the primary
coil. This magnetic field is transmitted through the core to the secondary coil where it induces a
current. An alternating current is required since direct current will not produced a changing
magnetic field – therefore no induced current can occur.
104
ACTIVITY 9: POWER SOURCES
105
Teacher’s Notes
Objective: Students will research power sources for the power grid. Lab groups will research
the advantages and disadvantages of an assigned power source and debate the pros and cons.
Time Requirement: Two to three 48 minute class sessions
Materials Needed: - Computer with Internet access and PowerPoint capabilities
- Power Source Research Packet( 1 for every student)
- Presentation rubric( 1 for every lab group)
Class Activities
 The teacher will distribute a power source research packet to every student. Together the
class will review the assignment as well as the types of power plant worksheet(located
within the packet)
 The teacher will break students into groups of four and assign each group one of the six
resources, coal, natural gas, solar, wind, hydroelectric, nuclear.
 The students will then be instructed to use recommended websites to research their
resource. They should use the presentation rubric and Lab sheet to guide them through
this research. Students should also begin developing a power point based on this
research. Remind students that a portion of their grade depends upon their ability to
equally distribute the workload. Suggest possible jobs for the students. Someone can be
in charge or PowerPoint production, another student could present the information, yet
another job is researcher.
 The research and presentation generation portions of this activity will require one and one
half days’ time. Students should be allowed the remainder of class as well as half of
tomorrow’s class to complete of this activity. Students can be encouraged to continue
their research at home.
DAY 2
 The first half of class will be dedicated to the completion of student presentations.(20-25
minutes)
 Students will then begin presenting their power points. The teacher should grade the lab
groups using the given rubric. This activity will take will require the remainder of today’s
class, as well as half of tomorrow’s class. Encourage students to take notes as other
groups are presenting. Remind them that they will be required to remember material
presented during today’s class, on tomorrow’s activity.(23-28 minutes)
DAY 3
 Students will finish presenting their PowerPoint presentations.(15-20 minutes)
 Students will then be asked to complete the Power Source Evaluation matrix in their lab
groups. They should evaluate each presentation as a village board member, not
competing engineer firms. Explain how the important attributes of each power source
have already been identified by the board president(you). Further more, a scale for
evaluating these attributes has been designed and provide for them. The students should
use this scale to rate each power source. Have the students add up the overall score for
each source. The source with the highest number should be our choice of power resource
for the new power plant.(5-10minutes)
 The teacher should then initiate a class discussion, using the questions on the back of the
matrix as a guide. Students should realize that the evaluation matrix is not a fair ranking
106
system, because it does not give priority to any item. Availability and cost of extraction
are ranked in identical fashions. Furthermore, students may question who decided which
attributes should be used for resource evaluation and who develop the ranking system.
An obvious missing attribute is the environment. This was purposely left out. Secondly,
the teacher should ask the students if this is a realistic scenario. Help the students to
understand that engineering firms are hired in similar manners and asked to make
presentations. One important component that was left out of this activity was that
students were NOT asked to provide disadvantage for their resources, i.e. environmental
concerns. This would be a violation of the engineering code of ethics. Have students
discuss if they think it is important for engineers to abide by a code, and why? Through
the discussion that follows students should realize that engineers need to present material
in an objective fashion so that fair decisions can be made, instead of presenting a
subjective viewpoint in hopes of gaining individual benefit. Explain to the students that
an ethical code exists for engineers and most jobs. Lastly, students should also question
how different groups view resource benefits. Have the students offer up suggestions on
which resource each subgroup would pick and the reasoning behind this selection. The
primary objective of this activity is not only to expose students to the different types of
power resources, but also to generate an ethical discussion regarding which power
sources we as a society should use( 18-28 minutes)
ASSESSMENT
 Presentation Rubric
 Teacher’s qualitative assessment of student participation in class discussion
RESOURCES
Rubric resource - http://www.teach-nology.com/web_tools/rubrics/
http://www.tesd.k12.pa.us/stoga/WebEnergy/Energyindex.htm#Introduction
www.thesolutionsite.com/lpnew_bin/UI_Metadata/public/26112 - 13k
http://www.nspe.org/ethics/eh1-code.asp
http://www.city-data.com/city/Orland-Park-Illinois.html
107
POWER SOURCE RESEARCH PROJECT
INTRODUCTION:
What is at the heart of the power plant? The generator plays a vital role, but it operation is
dependent on the input of energy. Where does the energy required to turn the turbine come
from? There are a variety of power sources, both renewable and nonrenewable that are used at
power plants. The attached worksheet highlights the major types of power plants and their
required resources. How do we decided which type of plant is right for our community? What
are the benefits and possible detriments of these power sources? These are questions you’ll
examine throughout the course of this activity
TASK:
The village of Orland Park requires more power. They are investigating the development of a
municipal utility from which to purchase power. This utility will require a power plant. The
village is researching their options for power sources, and has consequently hired developers
specializing in each power source to develop proposals. Your engineering firm has been
approached by one of these developers and asked to prepare a study on that power source for
proposal. Your task is to research the power resource and present a PowerPoint presentation to
the village board. Your group should use the attached lab sheet to guide this research.
EVALUATION
This project will count for two grades. Each portion of the grade is explained below.
1. Each group’s presentation will be evaluated based on the following rubric.
2. The group whose resource is selected by the village board will receive an A. All other
groups will receive a C.
Each group’s resource will be evaluated in terms of these viewpoints and receive an overall
score using a decision tree matrix. Based on the results of this matrix, the class will
determine the best power source for the new plant.
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PRESENTATION RUBRIC
NAMES__________________________________________________
POWER SOURCE: __________________________
40
Organization
Content
Accuracy
Visuals
Background
information on
Resource
30
20
10
Audience cannot
Student presents
Audience has
understand
information in
difficulty following
presentation
logical sequence
presentation
because there is no
which audience can because student
sequence of
follow.
jumps around
information
____
Most of the
The content is
Content is
All content
content is
generally
typically
throughout the accurate but there accurate, but
confusing or
presentation is
is one piece of
one piece of
contains more
accurate. There are information that information is
than one factual
no factual errors.
might be
clearly flawed or
error.
inaccurate.
inaccurate.
____
Student presents
information in logical,
interesting sequence
which audience can
follow.
.Student occasional
Student used visuals to
Visuals related to
used visuals that
reinforce screen text and
text and presentation rarely support text
presentation
and presentation
Student used no
visuals.
____
presentation presentation did
presentation has
presentation
made a minimal not even attempt
covered all
covered most of
attempt to cover
to cover
information
the information
information
information
necessary for
necessary for
necessary for
necessary for
understanding the understanding the
understanding understanding
resource.
resource.
the resource.
the resource
____
Students mumble,
incorrectly
pronounce terms,
and speak too
quietly for students
in the back of class
to hear. Gross
inequity in division
of work
____
Total---->
____
Students’ voices are
clear. Students
Students used a clear
pronounce most
voice and correct,
words correctly. All
Delivery and
precise pronunciation of
group members
Division of Work
terms. All members of
participate, however
group participated
some are more
involved than others
Teacher Comments:
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Students incorrectly
pronounce terms.
Audience members
have difficulty
hearing
presentation.
Apparent inequity
in division of work
POWER SOURCE RESEARCH PROJECT
LAB SHEET
Your lab group must research your assigned power resource. Below are a collection of useful
websites. You are encouraged to use these sites and to also gather additional information on
your resource using the search engines Google or Yahoo.
Power Sources – Good sites for all lab groups to gain information
http://www.factmonster.com/ce6/sci/A0860501.html
http://www.energy.gov/
http://www.eia.doe.gov/
Fossil Fuels
http://www.bydesign.com/fossilfuels/links/
http://www.ucsusa.org/general/404.html
http://www.energyquest.ca.gov/story/chapter08.html
Alternative Energy – alternatives to fossil fuels
http://www.altenergy.org/
http://www.energy.gov/
http://www.ucsusa.org/
http://www.pbs.org/wgbh/warming/beyond/
http://www.eren.doe.gov/
http://www.nrel.gov/
Geothermal
http://www.ucsusa.org/clean_energy/renewable_energy_basics/offmen-how-geothermal-energyworks.html
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Nuclear
http://www.howstuffworks.com/nuclear-power.htm
http://www.ucsusa.org/general/404.html
Hydropower
http://www.howstuffworks.com/hydropower-plant.htm
http://hydropower.inel.gov/
Wind Power
http://www.eren.doe.gov/RE/wind.html
http://www.awea.org/
http://www.wind-power.com/#Renewable
http://www.bergey.com/
Solar Power
http://www.solarelectricpower.org/
http://www1.eere.energy.gov/solar/pv_important.html
http://www.pvpower.com/
http://www.us.schott.com/photovoltaic/english/index.html
WHAT INFORMATION SHOULD THE POWER POINT CONTAIN?
1. An overview of how the resource is used to produce electricity
2. Provide information regarding the following
a. Capacity of power source in Megawatts. Keep in mind the population of Orland Park is
55,461 (+/-8.6%)
b. Cost to extract resource
c. Cost to refine or convert resource
d. Reliability of resource for long term use – percentage of time that facility is producing
electrical energy
e. Cost to transmit
3. A list of websites used for your research
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Things to consider:
The power plant does not need to be located in Orland Park. The power can be transmitted into
Orland Park via transmission lines. These lines would be the property of ComEd, and therefore
ComEd will require a fee for these lines. This cost needs to be incorporated into the cost to
transmit. The length of the transmission lines is proportional to the cost. Furthermore, as the
distance of transmission increases, so too does power losses ( I 2 R ) the transmission lines.
Therefore, as the distance from Orland Park increases so too much the power output, in order to
account for these losses. This issue should also be addressed under the cost to transmit as well
as the capacity portions of the presentation. . Plants which are located in Orland Park will be
cheaper because a transmission charge will not be necessary
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POWER SOURCE EVALUATION MATRIX
It is time to decide which power source we will use for our new power plant. How shall we
decide? Use can make use of a tool engineers use help them make decisions such as where to
build an airport or how to design a building. This process is referred to as multi-attribute utility
theory or MAUT for short. We will be using a simplified modification of this theory to help us
make our decision.
1. We must quantify various attributes of each resource using the scale below. Based on the
presentations, each lab group must assign a value for each attribute of every plant.
Capacity in Mega Watts
Cost to Refine or Convert
1) – does not meet required capacity for
population
2) – meets required capacity for population
1) more than $1,000,000
2) $750,000 - $1,000,000
3) exceeds required capacity for population 3) $500,000 - $750,000
4) less than $500,000
Reliability ( Capacity Factor)
Cost to transmit(transmission distance)
1) below 80%
1) more than 250 miles
2) 80%- 90%
2) 100 – 249 miles
3) above 90% unlimited
3) less than 100 miles
Cost to Extract
1) more than $1,000,000
2) $750,000 - $1,000,000
3) $500,000 - $750,000
4) less than $500,000
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Measure
Capacity
Cost to Transmit
Cost of extraction
Cost of
refinement/conversion
Reliability
Solar(PV)
Measure
Capacity
Cost to Transmit
Cost of extraction
Cost of
refinement/conversion
Reliability
Nuclear
SOLAR
COAL
WATER
Coal
WIND
GAS
Wind
Water
NUCLEAR
QUESTIONS FOR DISCUSSION
1.
2.
3.
4.
5.
6.
7.
8.
9.
Which power resource will our plant utilize?
Is this scenario for selecting a power source realistic?
Do you think it is fair that only the group whose resource was selected received an A?
What should we as a society do to safeguard against these scenarios?
Was the manner in which we ranked the attributes of the resources fair? Explain.
Which resource would a construction engineer most likely choose? Why?
Which resource would a business person most likely choose? Why?
Which resource would an environmentalist most likely choose? Why?
Which resource would a taxpayer most likely choose why?
114
Gas
TYPES OF POWER PLANTS
Uses coal, petroleum, or natural gas
Fossil Fuel Power Plant
Nuclear Power Plant
Uses uranium
Hydroelectric Power Plant
Uses falling water
Wind Power Towers
Uses wind
Solar Thermal Power Plant
Uses sun’s energy
Information found at
http://www.osha.gov/SLTC/etools/electric_power/illustrated_glossary/power_generation_plant.html
115
ENGINEERING CODE OF ETHICS
The following is an excerpt from the Engineering Code of Ethics
Fundamental Canons
Engineers, in the fulfillment of their professional duties,
shall:
1. Hold paramount the safety, health, and welfare of the
public.
2. Perform services only in areas of their competence.
3. Issue public statements only in an objective and
truthful manner.
4. Act for each employer or client as faithful agents or
trustees.
5. Avoid deceptive acts.
6. Conduct themselves honorably, responsibly, ethically,
and lawfully so as to enhance the honor, reputation,
and usefulness of the profession.
http://www.nspe.org/ethics/eh1-code.asp
116
POSTTEST
1. What does an engineer do?
2. How are scientists and engineers different?
3. Your boss at the restaurant has decided to add a new item to the menu, salad. He
wants you to write a procedure for making a salad so that he can give it to the cooks.
.
a. . What would your general process for making a salad look like?
c. Does making a salad require a design process? Why or why not?
c. Will everyone who comes up with a process for making a salad have
the same process?
117
4. If you are a consumer and order a salad at a restaurant would you want there to be a
set of rules or standards for making your salad? Why or why not?
5. Do you think engineers should follow a set of guidelines or rules while doing their respective
jobs? Why or why not?
6. Where does electricity come from?
7. What is 1 Ω equivalent to?
a.
1 J/s
b.
1 W/A
c.
1 VúA
d.
1 V/A
8. If the resistance in a constant voltage circuit is doubled, the power dissipated by that circuit
will
a.
increase by a factor of two.
b.
increase by a factor of four.
c.
decrease to one-half its original value.
d.
decrease to one-fourth its original value.
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9. What is the Circuit Symbol for a Battery?
10. . What type of meter measures Current?
11. . How is the meter which measures Current connected in Series or Parallel?
12. Which Equation connects Resistance, Current and Voltage?
13. Draw a Circuit with three Resistors connected in Series.
14. Draw a Circuit with three Resistors connected in Parallel.
15. Draw the Shape of a Magnetic Field around a Bar Magnet.
16. How can a Straight Wire produce a Magnetic Field?
17. What does a Circuit Breaker do?
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18. Where in the National Grid is induced current used?
19. What is the National Grid?
20. What does a Power Station do?
21. Give two Advantages of Nuclear Power.
22. Give one Disadvantage of Hydroelectric Power.
120