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Conceptual Physics Unit 6
Part III: Curriculum—Unit 6
Grade 8: Conceptual Physics
UNIT BACKGROUND
Unit Title:
Subject/Topic:
Key Words:
Unit Designer:
School District:
Work, Power, and Energy
Grade Level:
Conceptual Physics / Work, Power, Energy
Work, Power, Kinetic Energy, Potential Energy, Simple Machines, Efficiency,
Mechanical Advantage
Brent W. Maddin
Time Frame: 4 weeks
6 Weeks:
I.D.E.A. Academy
I.D.E.A. Academy
School:
8
3rd
BRIEF SUMMARY
This is the most packed unit of the year and may actually need more than four weeks to complete. In this
time, students will study the concepts of work and power (about 1.5 weeks), energy (1.5 weeks) and
simple machines (about 1 week). Students will learn about the differences between work and power and
then apply their knowledge in a lab where they compare their power to that of a beetle. Students then
investigate different forms of energy and specifically examine potential and kinetic energy and the law of
conservation of energy as it applies to roller coasters. If the instructor chooses, the rollercoaster
performances task could be replaced by three labs on potential energy, kinetic energy, and the
conservation of energy for which the student could choose one to write a formal lab report on. The unit
concludes as students will do a brief survey of simple machines and then examine what they do for
mechanical advantage and efficiency.
STAGE 1: DESIRED RESULTS
SCIDEA #
SCIDEA 240
SCIDEA 266
SCIDEA 269
SCIDEA 270
SCIDEA 232
SCIDEA 221
SCIDEA 222
SCIDEA 225
SCIDEA 268
SCIDEA 23
Unit Specific Standards
Knows that all energy can be considered to be either kinetic energy (energy of motion),
potential energy (depends on relative position), or energy contained by a field
(electromagnetic waves); energy can transform between the different types; can provide
examples of each** (KM-9-IV-2) (7.8 A, PHY.5 B)
Calculates speed, acceleration, momentum, force, work and power using mathematical
equations (IPC.4 A)
Analyze and calculate effects caused by changing force or distance in simple machines,
household devices, the human body, and vehicles (IPC.4 C)
Investigate, demonstrate, and calculate mechanical advantage and efficiency of levers,
motors, wheels and axles, pulleys and ramps (IPC.4 D)
Analyze the efficiency of energy conversions for production of electricity (IPC.6 C)
Knows that energy is a property of many substances (e.g., heat energy is in the disorderly
motion of molecules and in radiation; chemical energy is in the arrangement of atoms;
mechanical energy is in moving bodies or in elastically distorted shapes; electrical energy is
in the attraction or repulsion between charges) (KM-9-III-1)
Understands the law of conservation of energy and can calculate energy and momentum (i.e.,
energy cannot be created or destroyed but only changed from one form to another)** (KM9-III-2) (IPC.6 A, PHY.5 C & D)
Identifies, measures, and calculates energy transformations and gains/losses in heat**
(CHM.5 B,C)
Interprets evidence for work-energy theorem (PHY.5 A)
Knows the major external and internal sources of energy on Earth (e.g., the Sun is the major
external source of energy; the decay of radioactive isotopes and gravitational energy from
the Earth's original formation are primary sources of internal energy) (KM-1-IV-3)
Level of
Instruction
IPM
IPM
IPM
IPM
PM
M
M
IP
IP
P
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Conceptual Physics Unit 6
SCIDEA 166
SCIDEA 229
SCIDEA 238
SCIDEA 343
SCIDEA 373
SCIDEA 380
SCIDEA 230
SCIDEA 231
SCIDEA 233
SCIDEA 16
Differentiates between chemical and physical properties and changes in matter and relate to
transformation of energy** (IPC.8 A, CHM.4 A, CHM.5 A)
Knows and can give examples/evidence of byproducts resulting from the transfer of energy
in chemical and nuclear reactions (7.7 A)
Understands the concept of entropy (e.g., although the total energy of the universe remains
constant, matter tends to become steadily less ordered as various energy transfers occur; the
energy tends to spread out uniformly, thereby decreasing the amount of useful energy) (KM9-IV-1) (PHY.7 B)
Draw inferences from promotional materials for products and services (3.3 B, 4.3 B, 5.3 B,
6.3 B, 7.3 B, 8.3 B, BIO.3 B, CHM.3 B, PHY.3 B)
PowerPoint
Digital Cameras
Describes types of nuclear reactions describes their roles in medicine and energy production
(IPC.8 D)
Evaluates the commercial use of nuclear energy and the environmental issues associated
with nuclear wastes (CHM.9 C,D)
Investigate and compare economic and environmental impacts of using energy sources
(IPC.6 D)
Describes the interactions among solar, weather, and ocean systems (8.10 B)
P
P
P
P
P
P
P
P
P
R
On-Going Standards
SCIDEA 354
SCIDEA 319
SCIDEA 312
SCIDEA 314
SCIDEA 351
SCIDEA 384
SCIDEA 287
SCIDEA 300
SCIDEA 305
SCIDEA 309
SCIDEA 321
SCIDEA 323
Convert between English and metric units (meters --> kilometers) (CHM.2 C)
Knows that the work of science requires a variety of human abilities, qualities, and habits of
mind (e.g., reasoning, insight, energy, skill, creativity, intellectual honesty, tolerance of
ambiguity, skepticism, openness to new ideas). (KM-13-III-2)
Knows that conceptual principles and knowledge guide scientific inquiries; historical and
current scientific knowledge influence the design and interpretation of investigations and the
evaluation of proposed explanations made by other scientists (KM-12-IV-5)
Knows that investigations and public communication among scientists must meet certain
criteria in order to result in new knowledge and methods (e.g., arguments must be logical
and demonstrate connections between natural phenomena, investigations, and the historical
body of scientific knowledge; the methods and procedures used to obtain evidence must be
clearly reported to enhance opportunities for further investigation) (KM-12-IV-7)
Extrapolate on graphs to make predictions (6.2 C, 7.2 C, 8.2 C, BIO.2 C, CHM.2 D, PHY.2
C)
Excel (to organize, analyze and graph data)
Understands the nature of scientific explanations (e.g., use of logically consistent arguments;
emphasis on evidence; use of scientific principles, models, and theories; acceptance or
displacement of explanations based on new scientific evidence) (KM-11-III-2)
Knows that there is no fixed procedure called "the scientific method," but that investigations
involve systematic observations, carefully collected, relevant evidence, logical reasoning,
and some imagination in developing hypotheses and explanations (KM-12-III-1)
Establishes relationships based on evidence and logical argument (e.g., provides causes for
effects) (KM-12-III-6)
Designs and conducts scientific investigations (e.g., formulates testable hypotheses;
identifies and clarifies the method, controls, and variables; organizes, displays, and analyzes
data; revises methods and explanations; presents results; receives critical response from
others) (KM-12-IV-2) (3.2 A, 4.2 A, 5.2 A, 6.2 A, 7.2 A, 8.2 A, BIO.2 A, CHM..2 A, PHY.2
A)
Understands ethics associated with scientific study (e.g., potential subjects must be fully
informed of the risks and benefits associated with the research and their right to refuse to
participate; potential subjects must be fully informed of possible risks to community and
property). (KM-13-III-4)
Knows ways in which science and society influence one another (e.g., scientific knowledge
and the procedures used by scientists influence the way many individuals think about
themselves, others, and the environment; societal challenges often inspire questions for
scientific research; social and economic forces strongly influence which science research
programs are pursued and funded). (KM-13-III-6) (3.3 D, 4.3 D, 5.3 D, 6.3 D, 7.3 D, 8.3 D,
PHY.3 C, BIO.3 C, CHM.3 C)
IP
M
P
P
P
P
PM
PM
PM
PM
PM
PM
2
Conceptual Physics Unit 6
SCIDEA 329
SCIDEA 345
SCIDEA 346
SCIDEA 356
SCIDEA 297
SCIDEA 303
SCIDEA 334
SCIDEA 340
SCIDEA 358
SCIDEA 363
SCIDEA 367
SCIDEA 369
Knows that creativity, imagination, and a good knowledge base are all required in the work
of science and engineering. (KM-13-IV-6)
Write a Lab Report (Abstract, Problem, Hypothesis, Materials, Procedures, Observations,
Data (tables and graphs), Sample Calculations, Conclusions, Error)
Identify sources of error and recommend way to eliminate them
Flinn Lab Safety Contract (PHY.1 A, BIO.1 A, CHM.1 A)
Plans and conducts simple investigations (e.g., formulates a testable question, makes
systematic observations, develops logical conclusions) (KM-12-II-3) (K.2 B, 1.2 B, 2.2 B &
E, 3.2 C & D, 4.2 C & D, 5.2 C & D, 6.2 D, 7.2 D, BIO.2 D, CHM.2 E, PHY.2 D)
Knows that observations can be affected by bias (e.g., strong beliefs about what should
happen in particular circumstances can prevent the detection of other results) (KM-12-III-4)
Measure length (1.4 C, 2.4 B)
Represent measured values in appropriate units (1.4 C, 2.4 B)
Ruler – Centimeters and Inches
Stopwatch
Calculators
Meter sticks
PM
PM
PM
PM
R
R
R
R
R
R
R
R
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Conceptual Physics Unit 6
Conceptual Physics Unit 6:
Work, Power, Energy
Knowledge that is worth being familiar with
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Knows that in order for work to be done, an object must move a distance (266)
Knows which types of energy conversions are most efficient (232)
Knows that no machine can ever be 100% efficient (270, 232)
Relates chemical and physical properties and changes to transformations in energy (166)
Evaluates the efficiency of nuclear energy production and can cite some of the environmental impacts associated with it
and other forms of energy production (231, 233, 16)
Identifies major external and internal sources of energy on Earth (sun, decay of radioactive isotopes, gravitational energy)
and can give examples of byproducts made when this energy is converted (oxygen and water in photosynthesis and new
radiation during radioactive decay) (23, 229)
Can state the first law of thermodynamics and realizes that matter becomes less ordered (238)
Knows that work can change and object’s KE or PE according to the work-energy formulas W=KE and W=PE (268)
Knows how changing force or direction effects the mechanical advantage and efficiency in household devices (can opener,
bottle opener), the human body (joints), and vehicles (wheel and axles, gears) (269, 270)
Uses efficiency statistics on promotional material to draw information about quality of a product (343)
Knowledge & skills that are important to know & do
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Worth being
familiar with
Important to
know and do
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Enduring
Understanding
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Define all enduring and applied vocabulary
Can manipulate the equations W=Fd and P=W/t to solve for any
unknown quantity (266)
Knows the units on work and power (340)
Can design an experiment where the work and power for
students and beetles are measured and compared (354, 319, 312,
287, 300, 329, 297, 367)
Conducts a safe experiment so that the beetles and human
subjects experience no harm (321, 356)
Correctly uses stop watches, rulers and meter sticks to measure
time and length (334, 340, 358, 363, 369)
Can write a formal lab report containing tables, graphs, data
analysis and conclusions that must be evaluated by fellow
scientists (351, 384, 314, 305, 309, 345, 346)
Determines reasons why the information from the beetle
experiment would have applications outside the physics
classroom (323)
Can classify and differentiate between and give examples of
various types of energy (heat energy, chemical energy,
mechanical energy, and electrical energy) (240, 221)
Can manipulate the equations KE=1/2 mv2 and PE=mgh to solve
for any unknown quantity (225)
Uses the equations for KE and PE and the Law of Conservation
of energy to calculate energy transformations (225)
Can classify all simple machines as either levers or inclined
planes (269, 270)
Uses digital cameras to take pictures of simple machines around
school and uses those pictures to create a PowerPoint slide show
on simple machines (373, 380, 269, 270)
Can manipulate the equations for mechanical advantage for
various simple machines to solve for any unknown quantity
(269, 270)
ENDURING UNDERSTANDINGS: What enduring understandings are desired?
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Energy cannot be created or destroyed, just changed from one from to another. (240, 222, 225)
Simple machines make work easier by changing the distance or direction that force is applied. (269, 270)
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Conceptual Physics Unit 6
Unit 6 Vocabulary
Familiar Vocabulary
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Beetle (name_________________)
Horsepower
Peer Review
Chemical Property
Chemical Change
Physical Property
Physical Change
Relative Position
Heat Energy
Chemical Energy
Mechanical Energy
Nuclear Energy
Radioactive Decay
Byproduct
Isotope
Photosynthesis
1st Law of Thermodynamics
Hydroelectric Power
Wind Power
Elbow Joint
Knee Joint
Fulcrum
1st Class Lever
2nd Class Lever
3rd Class Lever
Gears
Promotional Material
Applied Vocabulary
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Joules
Watts
Energy Transformations
Gravitational Potential Energy
Entropy
Work-Energy Theorem
Mechanical Advantage
Efficiency
Force Input
Force Output
Work In
Work Out
Wheel and Axel
Lever
Screw
Incline Plane
Wedge
Pulley
Digital Camera
PowerPoint
Enduring Vocabulary
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Work
Power
Kinetic Energy
Potential Energy
Law of Conservation of Energy
Simple Machine
Unit 6 Biographies
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James Joule
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James Watt
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Conceptual Physics Unit 6
ESSENTIAL QUESTIONS: What questions will guide this unit and focus learning and teaching?
 If you are sitting at home pushing buttons on the remote control, how much work are you doing?
 In which instance am I doing more work: A) I carry 10 books across the room all at once or B) I carry
the 10 books across the room one at a time?
 Who is the most powerful person in the 8th grade?
 Who can do more work per body mass, you or a beetle?
 Describe what would happen to the physical properties of sand if you did work on it?
 Why do people use machines?
 Which simple machine: levers, pulleys or incline planes are most efficient?
COMMON MISCONCEPTIONS: What common misconceptions do students often have?
Misconception
Clarification
Students believe that carrying more a shorter
In reality, these values can be the same as long as
distance is more work than carrying less a greater
the product of Fxd is the same.
distance.
When calculating distance for work, students often The distance is really the vertical component of the
want to measure the distance of the object’s path
total distance as gravity is the only force that must
(i.e. up the diagonal up a ramp).
be overcome.
Students often believe that work depends on time.
Work is independent of time as evidenced by the
equation W=Fd. Power depends on time.
Students often believe momentum and KE are the
Not quite. Momentum is p=mv and KE=1/2mv2
same things.
Students often believe that simple machines reduce The force is not decreased, but rather is spread out
the amount of force needed to accomplish a task.
over a longer distance or redirected so that it is
easier to apply.
STAGE 2: ASSESSMENT EVIDENCE
Performance Task Summary (See Performance Task Blueprint for each task at the end of this unit)
 Performance Task #1— Working with Beetles: In this lab students will compare their work and
power to that of a beetle. By harnessing a beetle with a “sled” on which pennies are placed and rigging
up a similar apparatus for the students, it will be possible to find out the maximum amount of work for
each test subject. It will then be mathematically possible to determine which has a higher work:body
mass ratio.
 Performance Task #2— The Conservator: A New Six Flags Roller Coaster: Using popsicle sticks
and pipe insulation (cut in half) students will construct a roller coaster for a marble. The students will
be required to have certain elements in the coaster (hills, turns, loops) and are expected to be able to
calculate the potential energy and kinetic energy at any point along the coaster.
 Performance Task #3— Simple Machines at Home and School: At school, students will work in
teams using digital cameras to select examples of each simple machine around the school. They will do
the same at home, but make a sketch of each one. From each set, students will select one machine and
calculate its mechanical advantage and efficiency (if possible).
Student Self-Assessment
 Students will self-assess formal lab reports on their own rubric
 Students will use rubrics to peer-assess and self-assess their roller coasters and their simple machine
projects.
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Conceptual Physics Unit 6
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Conceptual Physics Unit 6
STAGE 3: LEARNING ACTIVITIES / RESOURCES
What sequence of teaching and learning experiences will equip students to develop and demonstrate
the desired understandings? Consider the WHERE elements from the student’s perspective
(Where is the work headed; Hook; Explore the subject in depth; Rethink, rehearse, revise; Evaluate)
#
Topic
Instructional Choice
Resources Needed
Essential Question: If you are sitting at home pushing buttons on the remote control, how much work are you doing?
Essential Question: In which instance am I doing more work: A) I carry 10 books across the room all at once or B) I carry the
10 books across the room one at a time?
Push on a wall and ask how much
1.
Work Demo
Demo
work is being done.
Objects to have students lift, stop
2.
Work and Power with Units
Lecture, Demos, Discussion
watches, meter sticks
3.
Work and Power
Whiteboarding, GP, IP
Problem Sets
Essential Question: Who is the most powerful person in the 8th grade?
Stopwatches, meter sticks, steps,
bathroom scale. Have students
4.
Work and Power Lab
Lab
calculate work and power for each
other.
Problem set on converting between
5.
Calculating Horsepower
Lecture, GP, IP
power and horsepower
Essential Question: Who can do more work per body mass, you or a beetle?
Beetles and People and treatment
6.
Ethics in Experimentation
Discussion
during experimentation, find a reading
if time permits
Performance Task #1: Working with Beetles
Beetle Data, Perhaps a reading from
7.
Why do Scientists Experiment?
Discussion
the Ig Noble Awards (Annals of
Improbable Research)
Essential Question: What will happen if you do work on sand?
Examples of physical properties:
8.
Physical Properties
Lecture, Discussion
mass, volume, temperature
Sand, Closed Containers,
9.
Discovering Mechanical Energy
Lab
Thermometers (Hewitt pg. 106)
Marble, Bowling Ball, Student
Deriving the Formula for Potential
10.
Demonstration
Volunteer to lie on the ground above
Energy
the different spheres.
11. Calculating Potential Energy
Lecture, GP, IP
Problem sets for PE
12. Calculating Kinetic Energy
Lecture, GP, IP
Problem sets for KE
Hook up a bowling ball on a chain
and attach it to the ceiling. Stand to
13. Law of Conservation of Energy
Demonstration
the side so the ball has maximum PE,
pull it almost to your nose and let go.
Don’t lean forward.
Calculations involving of the Law of
Problem sets involving energy
14.
Lecture, Discussion, GP, IP
Conservation of Energy
conservations
Applications involving of the Law of
15.
Discussion
Information on roller coasters
Conservation of Energy
Performance Task #2: The Conservator: A New Six Flags Roller Coaster
Essential Question: What would happen if two balls from Newton’s Cradle were pulled back and let go?
16. Energy Conversions
Demonstration/Discussion
Newton’s Cradle
Have students identify all of the other
17. Other Types of Energy
Discussion/Lecture
types of energy. Having examples of
each would be useful.
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Conceptual Physics Unit 6
18.
Converting Energy from One Form to
Another
Discussion
Readings and statistics on amount of
energy lost during different types of
conversions (nuclear into electrical vs.
hydro-mechanical into electrical)
Essential Question: Why do people use machines?
Have examples of the six types of
simple machines out for student to
19. Intro to simple machines
Discovery Walk
encounter and play with and answer
questions about.
Why use simple machines? How do
20. Simple Machines
Lecture
they relate to energy?
Using the machines from the station
21. Classification of Machines
Discussion
walk, classify each as either a type of
lever or incline plane.
Essential Question: Which simple machine: levers, pulleys or incline planes are most efficient?
Have examples of levers and pulleys
22. Anatomy of Pulley and Levers
Demonstration/Lecture
and name each of the parts and how
they basically operate.
Problem sets they show how to find
23. Calculating MA and Efficiency
Lecture, GI, IP
ME and Efficiency for each type of
machine.
Pulley Lab, Incline Plane Lab, Lever
24. Simple Machine Lab
Laboratory
Lab..students can choose one to write
up.
Performance Task #3: Simple Machines at Home and School
25. Unit Test
Test
Test
Connection to School-Wide Initiatives
Character Education (Trustworthiness, Respect, Responsibility, Fairness, Caring and Citizenship)
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When working with the beetles and each other, students need to exercise respect and caring for all
living creatures.
Empowerment Discussions
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Students will learn about the careers associated with roller coaster engineering.
Leadership
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Students will develop leadership qualities as they rotation through specified roles in the laboratory.
Every forth day, each student will be the leader of their cooperative group--they are the compound
commander.
Connection to IB Areas of Interaction
Approaches to Learning
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The ability to do methodical work is demonstrated when student use logic and a set method to study
the relative power of beetles and humans.
Self-sufficiency, responsibility and team spirit are demonstrated in the laboratory when students
collaboratively design their own experiments in a safe way. This is also demonstrated when the
students must select one of a series of labs to write up.
Students demonstrate their ability to communicate experiences in their formal lab reports and the
graphs and data tables they produce.
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Conceptual Physics Unit 6
Community Service
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There are no direct connections to community service in this unit.
Health and Social Education
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Students should make the connection between their body masses and the amount of work that their
bodies have to do. This is a great time to talk about the benefits of being fit—in a very scientific way.
Environment
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In this unit students will investigate the relative efficiencies of different types of energy conversions.
They should recognize the benefits associated with cleaner energy types.
Homo faber (Man the Maker)
Students should see the relationship between science and technology and what can be learned by
studying nature. For example, the beetles should have a greater mass to power ratio than the students
and therefore may provide insight into how to improve human creations.
Thoughts and Resources for the Future
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Add these as the unit is in progress…
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