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 (6)

#### 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
Level: Grades 11-12

#### References and Collections:

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 from Los Alamos National Lab, written for non-scientists, is a solid overview of fuel cell technology for teachers planning a unit on clean energy or alternative fuels.

Item Type: Reference Material
Level: General Audiences

This resource links to the Energy section of the Science Literacy Benchmarks published by the AAAS.  It is a statement of desired learning outcomes on the topic of Energy Transformations for grades 2, 5, 8, and 12.

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
Level: Grades 6-12

#### 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 transfer or conversion from 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
Level: Grades 9-12

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 was designed for students of high school physics, but could also be very useful as a refresher for middle school teachers.

Item Type: Interactive Tutorial
Level: Grades 8-12
Duration: 45 minutes

### What is Energy? (3)

#### Activities:

This interactive offers a host of tools to explore the relationships among force, work, and energy. You can control ramp angle, friction, and magnitude of force. Choose from different objects to run up the ramp: a box, a dog, a piano, and more. As students move objects of varying mass up an incline, they can adjust the angle of the ramp, friction, and applied force.  Can be modified to meet curriculum of grades 5-12. Note: Resource requires Java

Item Type: Interactive Simulation
Level: Grades 5-12
Duration: 1-2 Class Periods

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
Level: Grades 8-12

#### 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
Level: Grades 9-12

### Energy Forms and Sources (5)

#### 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. Highly recommended: Meets all 3 Dimensions of the NGSS for integrating the engineering design process in building, testing, and refining a device that converts energy from one form to another.

Item Type: Project-Based Learning
Level: Grades 6-12
Duration: 3-4 Class Periods

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. Also highly recommended. Cost is quite reasonable for a week-long maker project.

Item Type: Project-Based Learning
Level: Grades 6-12
Duration: 3-4 Class Periods

#### 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
Level: Grades 6-12

A fuel cell is a device that converts chemical energy directly to electrical energy, resulting in greater fuel efficiency and fewer emissions.  This overview of fuel cell technology was written by Los Alamos National Lab for non-scientists. It could serve as a great reference for teachers planning a unit on clean energy or alternative fuels or as a tutorial for high school students.

Item Type: Reference Material
Level: General Audiences

#### Student Tutorials:

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
Level: Grades 6-12

### Conservation of Energy (7)

#### Activities:

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
Level: Grades 9-12

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
Level: Grades 6-12

This mobile-friendly simulation is an HTML rewrite of the PhET fave "Energy Skate Park". In this version first explore an idealized system (no friction) and visualize conservation of energy as Energy Bar Graphs display changing kinetic and potential energy levels. Click "Friction" and observe the effects on the skater's motion. The bar graph changes to show kinetic energy being converted to thermal energy, resulting from friction.Note: This version is much simpler than the original Java version of Energy Skate Park, which introduces energy graphs and inputs to set gravitational constant. This version is more appropriate for middle school; the Java version (below) will be preferable to HS physics teachers.

Item Type: Interactive Simulation
Level: 6-12
Duration: One Class Period

This the original Java version of Energy Skate Park. It offers additional features not available in the "Basics" version, such as graphs of Energy vs. Position and Energy vs. Time. Students can change the gravitational constant to see how the motion would appear on different planets.

Item Type: Interactive Simulation
Level: Grades 10-12
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
Level: Grades 9-12

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:

This set of 35 clicker questions (with answer key) was developed by PhET Gold Star teacher Trish Loeblein for use in the high school classroom with the Energy Skate Park simulation. You can download it as a pdf or as a Power Point file with answer key. It is designed to elicit student understanding of three key things: 1) Relationship of kinetic and potential energy in a mechanical system, 2) Conservation of energy conservation in a system both with and without friction (adding friction introduces the concept of thermal energy), and 3) Relationship of the skater's mass, speed, and track configuration.

Item Type: Formative Assessment
Level: 9-12
Duration: One Class Period

### 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
Level: Grades 9-12
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
Level: Grades 9-12
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
Level: Grades 9-12
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
Level: Grades 9-12

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
Level: Grades 9-12

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
Level: Grades 9-12

### 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 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. Note: Only registered users can access the PhET teacher-created materials, but registration is free and easy.

Item Type: Student Lab Guide
Level: Grades 10-12

#### 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
Level: Grades 9-12

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? Resource requires Java

Item Type: Interactive Simulation
Level: Grades 5-12

### Renewable Energy Sources (7)

#### Lesson Plans:

We 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. Note: Only registered users can access the PhET teacher-created materials, but registration is free and easy.

Item Type: Student Guide
Level: Grades 10-12

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
Level: Grades 6-10
Duration: 2-3 Class Periods

#### Activities:

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

Item Type: Interactive Animation
Level: Grades 9-12
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
Level: Grades 6-12
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? Resource requires Java.

Item Type: Interactive Simulation
Level: Grades 6-12

#### 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
Level: Grades 6-12

#### 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
Level: Grades K-12