Editor selections by Topic and Unit

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## AP/Calculus-Based Physics:Conservation of Energy Units

Understanding the interconnectedness of the concepts of conservation of energy, momentum and angular momentum underpins the basis for much of physics. Units are not listed in a prescribed order.

### Teaching About Energy (10)

#### Activities:

This is a set of problems developed by Physics Teacher Resource Agents (PTRA), relating to radioactive decay and the energy released in fission reactions. It includes answer key and brief background information.

Item Type: Problem Set

One of the best ways for students to visualize Conservation of Energy is to create an energy pie chart or bar graph.  This cost-free web page allows them to select from one of five graph types:  bar, pie, line, area, or X/Y.  They can customize the patterns, colors, grids, and label choices, then print the final product. Editor's Note: Try letting students create their own energy graphs after exploring the Pendulum Energy Model (above).

Item Type: Digital Tool

#### References and Collections:

Do high school physics students understand when they should use concepts of energy conservation to solve problems?  Students involved in this research study had great struggles with this, even those with prior instruction on the topic. (R. Driver and L. Warrington, Phys. Educ. 20 (4), 171 (1985), WWW Document, (http://dx.doi.org/10.1088/0031-9120/20/4/308).

Item Type: Journal Article

A fuel cell is a device that converts chemical energy directly to electrical energy, resulting in greater fuel efficiency and fewer emissions.  This online report, written for non-scientists, is an excellent reference for teachers planning a unit on clean energy or alternative fuels.

Item Type: Reference Material
Level: General Audiences

One of the best websites we've found for exploring different sources of energy and the advantages/disadvantages of each. Sections include: fossil fuels, solar, wind and geothermal energy, hydroelectric power, nuclear, and biomass. Don't miss the sections on tidal energy and ocean wave energy! Each section provides video clips, images, and diagrams to help kids see how the processes work.

Item Type: Multimedia Collection

#### Student Tutorials:

Work-Energy bar charts are a conceptual tool which depict the amount of each form of energy within a system as it undergoes a particular motion or process.  This animated tutorial helps students understand the intricate relationship between work and energy, an area of common misconception.

Item Type: Interactive Tutorial

This five-part tutorial helps users analyze motion from the perspective of Work and Energy.  Explore potential energy, kinetic energy, and total mechanical energy with the help of descriptive text, sample problems with solutions, force diagrams, and links to related animations. Resource is appropriate for middle school teachers and for high school physics courses.

Item Type: Interactive Tutorial
Duration: 45 minutes

#### Assessment:

Energy is a scalar quantity and cannot be represented by vector arrows; thus it can be difficult to assess student understanding of the Law of Conservation of Energy.  In this model worksheet, students create energy bar graphs and flow diagrams to analyze what happens as energy is transferred and converted.

Item Type: Problem Set
Level: High School Physics

This model assessment on Conservation of Energy assesses both mathematical skills in solving problems as well as qualitative skills in creating energy bar graphs and flow diagrams.

Item Type: Test/Quiz
Level: High School Physics

Energy pie charts are a conceptual tool to help students understand the process of transferring energy into or out of a system.  This model worksheet gives students practice in system definition and in analyzing energy storage.

Item Type: Problem Set
Level: High School Physics

### What is Energy? (3)

#### Activities:

This page features animations of carts traveling at constant speed on three inclines of equal distance but varying slopes.  Which path requires the most energy?

Item Type: Interactive Tutorial

#### Student Tutorials:

The author of The Physics Classroom has tied together the concepts of work, power, and Conservation of Energy in this set of 6 interactive tutorials for high school students. It provides a good foundation for future understanding of the Work-Energy Theorem. This section is appropriate for Physics First, as well as high school physics courses.

Item Type: Interactive Tutorial

#### Assessment:

Energy is a scalar quantity and cannot be represented by arrows; thus it can be difficult to assess student understanding of the Law of Conservation of Energy.  In this model worksheet, students create energy bar graphs and flow diagrams to analyze what happens as energy is transferred and converted.

Item Type: Problem Set
Level: High School Physics

### Energy Forms and Sources (6)

#### Activities:

This resource gives step-by-step instructions for building a vertical axis wind turbine in secondary classrooms.  The 17-page construction plans may be freely downloaded and are organized for first-time builders.  A printable lesson plan is provided, as well as comprehensive background information on wind energy.

Item Type: Project-Based Learning

This resource gives step-by-step instructions for building a water-powered electric generator from plastic spoons.  The model closely resembles real micro-hydro designs, and can produce enough electricity to light a small light bulb.  Detailed background information and links to animated tours of hydroelectric power plants are included.

Item Type: Project-Based Learning

#### References and Collections:

For the teacher looking for an immersion experience in green energy for grades 6-12, this resource offers detailed labs with set-up instructions for constructing a wind turbine, solar oven, water-powered electric generator, and bio-gas generator.  Extensive content support is integrated throughout.

Item Type: Project-Based Learning

A fuel cell is a device that converts chemical energy directly to electrical energy, resulting in greater fuel efficiency and fewer emissions.  This online report, written for non-scientists, is a great reference for teachers planning a unit on clean energy or alternative fuels.

Item Type: Reference Material
Level: General Audiences

#### Student Tutorials:

This is a good model for students to interactively explore how masses and springs relate to potential energy and Hooke's Law. They can adjust the stiffness of the spring, the hanging mass, damping (friction) and gravitational constant. Energy charts are provided to analyze the changing potential and kinetic energy of each spring.

Item Type: Interactive Simulation

One of the best websites we've found for exploring different sources of energy and the advantages/disadvantages of each. Sections include: fossil fuels, solar, wind and geothermal energy, hydroelectric power, nuclear, and biomass. Don't miss the sections on tidal energy and ocean wave energy! Each section provides video clips, images, and diagrams to help kids see how the processes work.

Item Type: Multimedia Collection

### Conservation of Energy (10)

#### Activities:

Students explore conservation of energy by building ramps, jumps, and tracks for a skateboarder.  The relationship of kinetic and potential energy becomes clear through energy vs. time and position charts.

Item Type: Interactive Simulation

The motion of a pendulum is a classic example of mechanical energy conservation.  In this animated tutorial, energy bar graphs depict the changing ratios of kinetic-to-potential energy as the pendulum swings.

Item Type: Interactive Tutorial

One of the best ways for students to visualize Conservation of Energy is to create an energy pie chart or bar graph.  This cost-free web page allows them to select from one of five graph types:  bar, pie, line, area, or X/Y.  They can customize the patterns, colors, grids, and label choices, then print the final product.

Item Type: Digital Tool

Roller coasters offer an inherently interesting way to study energy transformation. This scaffolded activity lets students choose from 5 track configurations or create their own design, then observe the resulting motion. Energy bar graphs are simultaneously displayed as the roller coaster runs its course. Students can adjust the initial speed of the car, add friction, or switch to stepped motion to see the exact points at which kinetic and potential energy reach maximum and minimum levels. Includes lesson plan and student guide.

Item Type: Computer Model

This video-based activity recreates Galileo's "Pin and Pendulum" experiment to promote understanding of the law of Conservation of Energy. Students explore qualitative ideas in the first video, then expand those ideas through analysis of a second, longer video.

Item Type: Activity
Duration: One Class Period

#### Student Tutorials:

Work-Energy bar charts are a conceptual tool which depict the amount of each form of energy within a system as it undergoes a particular motion or process.  This animated tutorial helps students understand conservation of energy as they visualize the relationship between work and energy.

Item Type: Interactive Tutorial

In this five-part tutorial you will explore potential energy, kinetic energy, and total mechanical energy with the help of sample problems and solutions, force diagrams, and links to related animations. This tutorial is appropriate for secondary science teachers and for students of high school physics.

Item Type: Interactive Tutorial

#### Assessment:

Energy is a scalar quantity and cannot be represented by vector arrows; thus it can be difficult to assess student understanding of the Law of Conservation of Energy.  In this model worksheet, students create energy bar graphs and flow diagrams to analyze what happens as energy is transferred and converted.

Item Type: Problem Set
Level: High School Physics

This model assessment on Conservation of Energy assesses both mathematical skills in solving problems as well as qualitative skills in creating energy bar graphs and flow diagrams.  It could be an effective follow-up to the model worksheet above.

Item Type: Quiz/Test
Level: High School Physics

Energy pie charts are a conceptual tool to help students understand the process of transferring energy into or out of a system.  This high-quality assessment gives students practice in system definition and in analyzing energy storage.

Item Type: Problem Set
Level: High School Physics

### Energy Transformation (6)

#### Lesson Plans:

This four-day lesson module explores this question: how can we use nanotechnology and renewable energy sources to address skyrocketing global demand for fuel and electricity?  Students build & test a nanocrystalline solar cell and critically analyze how solar energy can be part of a global solution. Completely turn-key, with Power Point slides, pretest and post-test, and student infobooks.

Item Type: Lesson Plan
Duration: 3-4 class periods

#### Activities:

How do solar panels work to gather energy from the sun and transform it to electrical energy? In this inquiry-based lab, students work in teams to disassemble a calculator, evaluate the design and operation of its component parts, and improve functionality through redesign. The lesson specifically focuses on photovoltaic technology to get kids excited about semiconductor physics. Includes problem set.

Item Type: Lab Activity
Duration: Two Class Periods

For teachers doing a unit on photovoltaics, this Flash animation will help students visualize what happens at the atomic scale as captured photons are converted to electric current in the solar cell. Toggle between two types of solar cells: the traditional silicon semiconductor and the newer dye-sensitized cell. Kids will see that there's more than one way to excite an electron.

Item Type: Interactive Animation
Duration: 20-30 minutes

#### Student Tutorials:

This animated tutorial features a downhill skier and four energy bar graphs.  Students observe the transformation of energy from potential to kinetic during the descent.  The end of the run is unpacked snow and the skier loses total mechanical energy (TME) to the dissipative force of friction.

Item Type: Interactive Tutorial

This tutorial features an animated roller coaster with moving bar graphs that depict kinetic and potential energy as the car descends and climbs. It is an example of a system in which TME (Total Mechanical Energy) remains the same during the course of the motion.

Item Type: Interactive Tutorial

The motion of a pendulum is a classic example of mechanical energy conservation.  In this animated tutorial, energy bar graphs depict the changing ratios of kinetic-to-potential energy as the pendulum swings.

Item Type: Interactive Tutorial

### Interactive Problem Solving (5)

#### Activities:

Students are given a rough design for a bungee jump from a 20m tower. They work cooperatively to figure out parameters for a safe jump, using principles of conservation of energy and gravitational potential energy. While some information is given, they must research certain aspects, such as the medically-recommended maximum acceleration for an untrained jumper. Teachers who register on the web site have free access to a complete instructor's guide.

Item Type: Problem-Based Learning
Level: High School Physics
Duration: Two Class Periods

Students work cooperatively to investigate an accident: a small car is struck broadside by a vehicle more than double its mass. The students must determine whether either driver engaged in reckless driving. More than one strategy can be used to solve the problem, which requires students to find the coefficient of friction on the roadway and determine the velocity of each vehicle upon impact and before braking. (It will be interesting to see if students choose the Work-Energy Theorem in solving.)  A complete instructor's guide is available cost-free to teachers who register on the web site.

Item Type: Problem-Based Learning
Level: High School Physics
Duration: 1-2 Class Periods

#### Student Tutorials:

This scaffolded homework problem is an excellent way to promote student understanding of when to use the Work-Energy Theorem to simplify problem solving.  This problem involves a truck traveling on a straight road, both with and without a payload.  The author takes the student step-by-step through a Socratic format of conceptual analysis, strategic analysis, and finally, setting up the equations.

Item Type: Interactive Problem
Level: High School Physics

Like the problem above, this scaffolded homework problem helps beginning students understand how to use the Work-Energy Theorem to solve problems which would be difficult or impossible using the kinematic equations.  It features a bobsled making a double-hill run.  Students are guided every step of the way in concept formation, strategic analysis, and how to do the math.

Item Type: Interactive Problem
Level: High School Physics

Try this homework problem as an extension of  the two above.  It involves a cart and block connected by a string passing over an ideal pulley.  Students choose whether to solve the problem using Newton's Second Law or the Work-Kinetic Energy Theorem.  Extensive help is offered for either choice.

Item Type: Interactive Problem
Level: High School Physics

### Global Issues Related to Energy Resources (3)

#### Lesson Plans:

We highly recommend this inquiry-based student lab, developed by a high school teacher for use with the PhET Greenhouse Effect simulation (see link under Activities below). The experimental question: "Which greenhouse gas is the best absorber of infrared photons?" Students use Photon Absorption section of the sim to shoot infrared and visible photons from a virtual emission gun. They can adjust levels of each gas to build their own atmospheric conditions. Comprehensive rubric is included.

Item Type: Student Lab Guide

#### Activities:

This student activity explores energy flow and conservation and was developed to help students make responsible choices in use of energy resources. It is part of a workshop manual on Energy by the PTRA, (Physics Teacher Resource Agents).

Item Type: Lesson Plan

This versatile simulation can be adapted for upper elementary, middle school, and high school. In its simplest form, kids can investigate greenhouse gases that were present in the last Ice Age, in the year 1750, at the present time, and at a point in the future. High school students can adjust levels of 4 atmospheric gases, then "shoot" infrared and visible photons into the atmosphere. How does the balance of gas levels influence photon absorption?

Item Type: Interactive Simulation

### Renewable Energy Sources (7)

#### Lesson Plans:

We highly recommend this simulation-based activity, developed by a high school teacher for use with the PhET Greenhouse Effect simulation (see link under Activities below). The experimental question: "Which greenhouse gas is the best absorber of infrared photons?" Students use Photon Absorption section of the sim to shoot infrared and visible photons from a virtual emission gun. They can adjust levels of each gas to build their own atmospheric conditions. Comprehensive rubric is included.

Item Type: Student Guide

The sun is the ultimate renewable energy source. This page provides step-by-step directions for constructing a solar oven that really cooks --  using simple, easily-obtained materials. Includes pattern for building the oven, detailed background information, and construction plans for student use.

Item Type: Project-Based Learning
Duration: 3-4 Class Periods

#### Activities:

How does a solar panel convert sunlight into electrical current? This interactive Flash tutorial provides a close-up look at each layer of the basic solar panel to show how electrons are energized when sunlight strikes the cell.

Item Type: Interactive Simulation
Duration: 20 minutes

Thought-provoking video takes a realistic view of the promise and challenge of solar power. It explores how solar energy is being currently used to power homes and businesses, and presents research into new methods for implementing solar technology. Free download.

Item Type: Video
Duration: 50 minutes

This versatile simulation can be adapted for upper elementary, middle school, and high school. In its simplest form, kids can investigate greenhouse gases that were present in the last Ice Age, in the year 1750, at the present time, and at a point in the future. High school students can adjust levels of 4 atmospheric gases, then "shoot" infrared and visible photons into the atmosphere. How does the balance of gas levels influence photon absorption?

Item Type: Interactive Simulation

#### Content Support For Teachers:

One of the best websites we've found for exploring different sources of energy and the advantages/disadvantages of each. Sections include: fossil fuels, solar, wind and geothermal energy, hydroelectric power, nuclear, and biomass. Don't miss the sections on tidal energy and ocean wave energy! Each section provides video clips, images, and diagrams to help kids see how the processes work.

Item Type: Multimedia Collection

#### Student Tutorials:

Help your students visualize what's going on when atoms undergo "excitation" and emit wave packets of light called photons. This set of classroom-tested computer simulations is highly recommended for promoting understanding of atomic processes in photon emission. Teachers: free registration allows your students to capture data, take snapshots, and submit work.

Item Type: Computer Modeling
Level: High School Physics
Duration: Two Class Periods

### Special Collections on Energy Education (1)

#### References and Collections:

The NEED Project is a national initiative to bring innovative curriculum materials in energy education to teachers and learners from the primary grades through college. At the core of the project's work are the portfolios of 120+ comprehensive curriculum guides on forms of energy, renewable and nonrenewable sources of energy, electricity, and fuel efficiency. Don't miss the interactive maps and Question Bank for customizing your assessments.

Item Type: Collection