Download Unit Plan: Energy

Physics
Unit One: Energy
Standards
Focus Standard:
SP2. Students will evaluate the significance of energy in understanding the structure
of matter and the universe.
a. Relate the energy produced through fission and fusion by stars as a driving force
in the universe.
b. Explain how the instability of radioactive isotopes results in spontaneous nuclear
reactions.
SP3. Students will evaluate the forms and transformations of energy.
a. Analyze, evaluate, and apply the principle of conservation of energy and
measure the components of work-energy theorem by
• describing total energy in a closed system.
• identifying different types of potential energy.
• calculating kinetic energy given mass and velocity.
• relating transformations between potential and kinetic energy.
b. Explain the relationship between matter and energy.
f. Analyze the relationship between temperature, internal energy, and work done in
physical system.
g. Analyze and measure power.
Enduring Understanding
1. Energy exists in various forms and can be transformed from one form to
another (Law of Conservation of Energy).
2. The mechanical energy of a system is the sum of its kinetic and potential.
3. Kinetic and potential energy are descriptions of the forms that energy can
have.
4. Work is the result of the displacement of an object under the action of a force.
5. There is a relationship between matter and energy in the equation E = mc2.
6. Vast amounts of energy are produced in fission and fusion reactions.
7. Nuclear fission and fusion are the processes that create the array of elements
in the universe.
8. Power is the amount of energy used by a system in a given unit time.
9. Electrons are outside the nucleus and the protons and neutrons are located
inside the nucleus.
10. Radioactivity is the process of sequential steps by which unstable radioactive
isotopes decay into stable isotopes.
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Concepts
Energy transformations, conservation of energy, closed system, kinetic energy,
gravitational potential energy, electric potential energy, elastic potential energy, matterenergy relationship, conservation of momentum, elastic collisions, inelastic collisions,
structure of matter, formation of matter, fission, fusion, radioactivity, work, power.
Language
Energy transformations, potential energy, kinetic energy, conservation of energy, electric
potential energy, elastic potential energy, gravitational potential energy, work, force,
gravity, closed system, matter, structure of matter, formation of matter, fission, fusion,
radioactivity, power, significant figures, calculate, experiment, precision measure,
accuracy, SI units, describe, scientific notation, conclusion, hypothesis, data, contrast,
compare, variable, infer, analyze, predict, interpret.
Possible Labs
Lab Name
Work-Energy TheoremSpring Constants and Energy
The Bungee Jumper:
Conservation of Energy
Location
http://www.frontiernet.net/~jlkeefer/jumpup.html
http://www.frontiernet.net/~jlkeefer/bungee.html
Lab: Down the Hill
Lab-Down The Hill sim.doc (Roudebush)
Popper Lab
Energy of Toys (Murray)
Radioactivity Lab
nuclearradioactivity.doc
Work and Power Lab
Work and Power Lab.pdf
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Sequence of Activities, Tasks, and Assessments for Unit
E.Q. #1 How are humans dependent on transformations of
energy? SP3a
Understandings:
 Energy exists in various forms and can be transformed
from one form to another (Law of Conservation of
Energy).
 Work is the result of the displacement of an object under
the action of a force.
Day 1
Intro to
Energy
Begin with Carousel Activity. Encourage students to think about the
nature of energy. The students begin by developing understandings
about the different forms of energy (i.e. Kinetic and Potential).
Students then connect these concepts to develop an understanding
about the law of conservation of energy. As a teacher, try to pick out
students’ misconceptions.
Continue uncovering students’ beliefs about energy.
 Have students brainstorm different types of energy.
 Demonstrate “hand-crank generator”
 Have students brainstorm energy transformations.
Students will complete “Energy of Toys” activity (c/o Jaclyn
Murray). Provide students with the following equations:
 (Gravitational Potential Energy) GPE=mgh
 (Kinetic Energy) KE= 1/2mv2
 Elastic Potential Energy = 1/2kx2
Summarizing: What types of energy did you observe in the toys?
What type of energy transformations did you observe in the toys?
Homework: Read Chapter 5; Section 1

Doing work on sand-page 147 Conceptual Physics
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E.Q. #1 How are humans dependent on transformations of
energy? SP3a
Understandings:
 Energy exists in various forms and can be transformed
from one form to another (Law of Conservation of
Energy).
 Work is the result of the displacement of an object under
the action of a force.
Introduce Work
Ask students, “What is energy?” At least one student will reply,
“Energy is the ability to do work.” That’s a great definition, but does
it mean? What is work?
Day 2
Work
In physics, work has a particular meaning. Consider the following
situations:
 A student holds a heavy chair at arm’s length for several
minutes.
 A student carries a bucket of water along a horizontal path
while walking at constant velocity.
Both of these situations require effort, but in neither of them is work
being done on the object.
Work is done on an object when a force causes a displacement.
Teach basic concepts of work using PowerPoint, “Work, Power, and
Energy”.
The work done on an object by a force is equal to the component of
the force along the direction of motion multiplied by the distance the
object moved:
W = Fd.
 Complete practice problems.
 What are the units for work?
 Explain the differences between positive and negative work.
Summarizing: (see energyslides.ppt)
1. It is said that energy is the ability to do work, then what is
work?
2. Explain two examples when (students can work in pairs):
a. work is postive.
b. work is negative.
c. work is zero.
Homework: Answer 12 and 4 on page 162 and 1, 5, and 6 on page
163.
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E.Q. #1 How are humans dependent on transformations of
energy? SP3a
Understandings:
 Energy exists in various forms and can be transformed
from one form to another (Law of Conservation of
Energy).
 The mechanical energy of a system is the sum of its
kinetic and potential.
 Kinetic and potential energy are descriptions of the
forms that energy can have.
Day 3
Kinetic
Energy
Ask students, “What is kinetic energy?” (see energy slides)
Show slides
a. think and rank
b. kinetic energy equation
c. what do you think
d. relative motion
Then, show selections of video by professor Richard Muller “Atoms
and Heat” http://www.youtube.com/watch?v=6ysbZ_j2xi0
What is kinetic energy related to:
 mass
 velocity squared
Work out some conceptual questions.
 ???????
Mathematically kinetic energy is
KE = 1/2 mv2
Work out some mathematical problems.
 Sample problem B
Student Practice
 1-5 on page 166
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E.Q. #1 How are humans dependent on transformations of
energy? SP3a
Understandings:
 Energy exists in various forms and can be transformed
from one form to another (Law of Conservation of
Energy).
 The mechanical energy of a system is the sum of its
kinetic and potential.
 Kinetic and potential energy are descriptions of the
forms that energy can have.
Major Concept: Kinetic energy is energy of motion. The kinetic
energy of an object equals the work that was needed to create the
observed motion. This work can be related to the net force applied to
the object along the line of the motion. The work done on an object
by a force is equal to the component of the force along the direction
of motion multiplied by the distance the object moved:
W = Fd.
The work needed to accelerate an object of mass m from rest to a
speed v is 1/2 mv2. This quantity is defined as the kinetic energy E.
The units of energy are joules, in which 1 joule = 1 kilogram-meter
Day 4-5
squared per second squared (1 kg-m2/s2) = 1 newton-meter. Energy is
Work-Kinetic a scalar quantity, meaning that energy has a magnitude but no
direction.
Energy
Theorem
Teaching Strategies:
DAY ONE:
I. Atwood machine Demo:
a. Ask questions about the change in KE,
b. forces acted on the cart,
c. and work done on the cart.
d. Can Students make the connection between work and
change in kinetic energy?
II. Work some example problems—simpler ones. I’ll think out
load.
III. Teach the 15-pointer rubric for problem solving.
IV. Students work problems in book.
V. Summarizing: Students complete a timed 15-pointer.
DAY TWO:
VI. Go over 15 pointer, address concerns.
VII.
Students work through two more problems. One in a
group and one individually.
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Alternate Lessons:
I.
Students will complete “Popup Toy Physics” activity (c/o
Jaclyn Murray).
*
II.
Go to the computer lab and have students read and
interact with the physics classroom website:
http://www.physicsclassroom.com/Class/energy/u5l2a.cf
m
Summarizing: Students answer these two questions in pairs:
1. A satellite is in circular orbit above the Earth’s surface. Why
is the work done on the satellite by the gravitational force
zero? What does the work-kinetic energy theorem predict
about the satellite’s speed?
2. When the brakes of a car are locked, the car skids to a stop.
How much farther will the car skid if it’s moving 3 times as
fast?
Homework: Answer 1,2, and 4 on page 168
E.Q. #1 How are humans dependent on transformations of
energy? SP3a
Understandings:
 Energy exists in various forms and can be transformed
from one form to another (Law of Conservation of
Energy).
 The mechanical energy of a system is the sum of its
kinetic and potential.
 Kinetic and potential energy are descriptions of the
forms that energy can have.
Day 6
Potential
I. Potential Energy
Energy / GPE Brainstorm: In 60 seconds, list as many types of potential energy as
you can. Lecture on the three types of potential energy we are
concerned with:
 chemical potential energy
 elastic potential energy
 gravitational potential energy
II. Gravitational Potential Energy
Explain it conceptually and get into some mathematical problems.
1. If you do 100 J of work to elevate a bucket of water, what is
*
This activity worked well last year.
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its gravitational potential energy relative to its starting point?
2. What would be the gravitational potential energy be if the
bucket were raised twice as high?
3. Look in thinking physics.
III. Explain it mathematically. DO SOME PROBLEMS.
1. GPE
2. KE
3. Conservation of Energy
4. Work
5. Work Kinetic Energy Theorem
Summarizing Strategy:
 Provide two examples/situations of chemical potential
energy.
 Provide two examples/situations of elastic potential
energy.
 Provide two examples/situations of gravitational potential
energy.
E.Q. #1 How are humans dependent on transformations of
energy? SP3a
Understandings:
 Energy exists in various forms and can be transformed
from one form to another (Law of Conservation of
Energy).
 The mechanical energy of a system is the sum of its
kinetic and potential.
 Kinetic and potential energy are descriptions of the
forms that energy can have.
Day 7-9
Activating Strategy: Bowling Ball Demo
Law of
Conservation Instructional Strategies:
of Energy / DAY ONE:
I. 20 Questions: I go through five slides at a time. Students
Mechanical
discuss and answer the questions as a group.
Energy
II. I’ll then go through a series of slides about conservation of
energy. I’ll ask students questions about them.
III. Students will then solve two problems in groups step-by-step.
DAY TWO:
IV. Students will work slowly through the 5 problems in the
book about conservation of energy.
DAY THREE:
V. I’ll have students work through a WS of mixed energy
problems.
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a. They’ll first have to figure out what type of problems.
b. Then they’ll solve them.
Summarizing Strategy:
Students will complete a time 15-pointer about conservation of
energy.
QUIZ: Next Day: Work-Kinetic Energy Theorem and Conservation
of Energy/
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E.Q. #1 How are humans dependent on transformations of
energy? SP3g
Understandings:
I. Power is the amount of energy used by a system in a given
unit time.
Activating Strategy:
What’s the difference between a 40 Watt bulb and a 60 Watt bulb?
Why? What does that have to do with power?
Teaching Strategy:
Day 10
Power
I. Ask students:
I. What is power? Scientific Definition vs. Everyday
Definition?
II. How is power different from energy? Are they
different?
III. How is power related to work?
IV. What is the mathematical formula for solving power?
V. What are the units for power?
II. Work and Power Lab
III. Students Answer and discuss questions on lab.
Power Problems:
1. If a person does 6000 Joules of work in one minute, what
power has he?
2. A bulldozer does work at a rate of 12 000 000 N every
minute. How powerful is it?
3. A car with a forward force of 6000 N drives a distance of 1
kilometer in 1 minute. How much power does it have?
4. If the athlete in Q5 ran up the stairs in 3.5 seconds. How
powerful is she?
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E.Q. #3 Why are we unable to do any nuclear experiments in
physics this year? SP3b, SP2a
Understanding:
 There is a relationship between matter and energy in
the equation E = mc2.
 Vast amounts of energy are produced in fission and
fusion reactions.
Activating Strategy: Have students brainstorm five things they
know about nuclear energy and radiation. Follow up this activity
with a discussion about this question: “What do you think E=mc2
means?
Day 11/12
E=mc2
View “Einstein’s Big Idea.” Assign a 1-2 page essay in which
students explain the importance of Einstein’s Big Idea and the
important contributions that lead to Einstein’s development of
E=mc2. The paper will be due two days after the completion of the
movie.
Summarizing Strategy: Assign each pair of students a contributing
scientist in the film. Have them briefly report to the class:
 Their scientist’s contribution.
 Their scientist’s time period.
 How did their scientist’s contribution assist Einstein in the
development of his idea?
Homework: Read Pages 790-794; Answer the following two
questions:
 What force holds the nucleus together?
 Why are some nuclei unstable?
 How do neutrons help to stabilize the nucleus?
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E.Q. #3 Why are we unable to do any nuclear experiments in
physics this year? SP2a,SP2b
Understanding:
 Vast amounts of energy are produced in fission and fusion
reactions.
 Nuclear fission and fusion are the processes that create the
array of elements in the universe.
Day 13
Fission and
Fusion
Activating Strategy:
Give Students Frayer Diagram Allow them a few minutes to fill them in based on memory.
 Then allow them to use their books.
 Discuss.
Lesson
Short Lecture: Fission and Fusion
Review for test.
Day 14
Test
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