Teacher Notes for Work and Energy

 

 

Unit Overview

We estimate this to be a 11-day unit. The unit will blend concepts of work, energy, and power with the mathematics associated with these concepts. An additional day should be added for an exam. There is one primary goal in this unit. It could be worded in a variety of ways. We have chosen the following wording.
 
Much of the instruction, the labs, the activities, the problems, etc. of this unit could be attached to this broad implication of the law of energy conservation. Whether the student is constructing a work-energy bar chart, performing a lab investigation, or solving a problem on a CalcPad problem set or in a Concept Builder, they are keeping track of energy to determine how it changes form and/or crosses the boundary of the system. 


 

Labs

We have proposed three labs for this unit. Since two of these do not have any Teacher's Guides available, we will supply some notes here. Additional details are on our Lab Page for this unit.

Lab 1: Lab 1 is identical to a lab that we have used for our other courses. We have provided a link to the Teachers Guide on our Lab page.

Lab 2: Lab 2 requires the use of a 12-inch ruler (with a groove down its middle), a marble, a 3"x5" note card, a meter stick, and a set of six Dominoes. Students use the ruler and the Dominoes to build a ramp and roll the marble down the ruler. The marble strikes the "plow" (a half note card folded into a V) at the bottom of the ramp and plows it across the table or floor a measurable distance. There are two parts to the lab. In Part A, students alter the release location of the marble along a 3-Domino ramp and examine the effect of release location upon the distance the plow is moved (before the marble stops rolling). In Part B, students build a 6-Domino ramp and determine by trial-and-error which release locations will result in the same plow distances that were measured in Part A. Students look for patterns in the data and answer the questions posed in the Purpose.

Lab 3: Lab 3 requires the use of a low-friction cart, a sturdy metal track, motion detectors, and a computer interface system. Students give the cart a push from the bottom of the track. The cart rolls up the track and back down. The motion detector detects the speed and height of the cart. KE, PE, and TME values can be calculated for a specified number of locations and compared to one another. BONUS: use the software to plot KE vs. time, PE vs. time, and TME vs. time plots. 

 

The Calculator Pad

We have provided four CalcPad assignments. Each assignment consists of 4-6 highly scaffolded (mostly) problems that step students through the logic of work and energy. All problems were customized for Conceptual Physics students from existing problems. The value of g used in the problems is 10.0 N/kg. Numerical information is still randomized but the values are gentler-looking values. The scaffolding will insure the highest likelihood of success and drive home the concept of momentum conservation by the system.

For teachers who wish to provide some problems with less scaffolding or even no scaffolding, you will find plenty of them in the Work and Energy chapter of our Calculator Pad. With a Task Tracker account, you can easily add problems to the sets we have provided for the Conceptual Physics course. You will find directions and video walk-throughs in the Teacher Resources section of your account. With the Task Tracker account, you can even add additional problem sets if you would like. There's no shortage of problems around The Physics Classroom and using the Calculator Pad with Task Tracker gives you control over how you can take advantage of them.


 

NGSS and the Science Reasoning Center

Energy is a big part of the Next Generation Science Standards. For those of us who teach Physics, it is both a Disciplinary Core Idea and a Crosscutting Concept. Our Science Reasoning Center is packed with interactive activities that emphasize science reasoning skills in the context of content. Put another way, you will find numerous activities that lie at the intersection of a disciplinary core idea, a science and engineering practice, and a crosscutting concept. The Energy section of our Science Reasoning Center includes numerous activities that would be of interest to those using an NGSS curriculum as well as those using any Physics curriculum. Here are a few of our favorites:
 

1. Push the Plow
   This five-part activity addresses student's ability to understand the design of an experiment, to identify evidence-based claims, to use proportional reasoning skills to determine relationships between variables, and to predict the result of additional trials.
2. Energy on an Inclined Plane
   This five-part NGSS activity targets a student's ability to make decisions regarding the design of an investigation, perform energy calculations from collected data, use an energy model to interpret the findings and to describe and explain the energy changes that are occurring, and evaluate a collection of claims regarding energy associated with the phenomenon.
3. Modeling Roller Coasters
   This NGSS-inspired activity challenges students to develop and use energy models to explain how energy is transformed between kinetic and potential energy. Exercises within the task include three Matching Pair exercises, three Paragraph Completion exercises, a Ranking Task exercise, a Table Completion exercise, and a Law Breaker exercise.
4. Hot Wheels Stopping Distance
   This NGSS-inspired activity challenges students to plan an investigation, to identify the effect (both qualitatively and quantitatively) of one variable upon another variable, to use the pattern in the data to make predictions by interpolation and extrapolation, to apply the speed-stopping distance relationship, and to use an energy model to explain the experimental results.

 

Other Resources

There are a few resources that we did not list in our Lesson Plans and Learning Outcomes and Activities that you may find to be very helpful. These include:
 

1. Minds On Physics: Mission WE6 on Energy Bar Charts
   Students utilize a bar chart and the work-energy relationship to analyze a physical situation and develop an equation which relates the energies of the initial and final states of a motion.
2. Minds On Physics: Mission WE7 on Mechanical Energy Conservation
   Students identify the basic principles of and the conditions required for energy conservation and apply the principles of energy conservation to a variety of physical situations.
3. Minds On Physics: Mission WE9 on Work and Energy Conversions
   Students identify the conditions in which mechanical energy is not conserved and demonstrate an understanding of the distinction between energy conservation and non-conservation.
4. Science Reasoning Center: Push the Plow
   While it was mentioned above, we want to give extra emphasis to the value of the Push the Plow Science Reasoning activity. It would provide a great follow-up to Lab 2.
5. Science Reasoning Center: Modeling Roller Coasters
   Once more we are highlighting what was mentioned in the previous section. Students love learning about the application of Physics to roller coasters. The Modeling Roller Coasters activity provides many great applications.
6. Concept Builder: Work
   Students identify whether positive, negative, or zero work is being done; they identify the force that is doing the work; and they describe the energy transformation associated with such work.
7. Concept Builder: LOL Charts
   Students use an energy bar chart to describe how energy is stored, transferred, and/or conserved for a variety of physical situations.
8. Physics Interactives: Kinetic Energy
   This simulation provides students a rich, interactive environment for investigating relationships between the force exerted on an object, the distance over which the force acts, and the speed and kinetic energy that the object acquires.

 

 

Teacher Presentation Pack

Our Teacher Presentation Pack is loaded with a collection of Slide Decks and animations for use in your classroom. Once downloaded, they are fully modifiable and customizable. They would allow you to quickly pull up a Slide for discussion in class or to show a quick animation. It may be a worthwhile investment, particularly if you are an early-career or cross-over Physics teacher.



 

Also Available ...

Physics teachers may find the following for-sale tools to be useful supplements to our Lesson Plan and Pacing Guide section:

 

1. Task Tracker Subscription (annual purchase)
   A subscription allows teachers to set up classes, add students, customize online assignments, view student progress/scores, and export student scores. Task Tracker accounts allow your students to begin assignments in class or at school and to finish them at home. View our Seat and Cost Calculator for pricing details.
    
2. The Solutions Guide
   We publish a free curriculum with >200 ready-to-use Think Sheets for developing physics concepts. The Solutions Guide is a download containing the source documents, PDFs of source documents, and answers/solutions in MS Word and PDF format. An expanded license agreement is included with the purchase. (Cost: $25 download)
    
3. Teacher Presentation Pack
   This is a large collection of downloadable content packed with nearly 190 Microsoft PowerPoint slide decks, the corresponding Lesson Notes (as PDF and fully-modifiable MS Word format), about 170 animations (in .gif, .png, and .mp4 file formats), a countless number of ready-to-use images (including the original source documents that would allow for easy modification of those images), and a license that allows teachers to modify and use all the content with their classes on password-protected sites (such as course management systems).  (Cost: $40 download)
    
4. Question Bank
   We distribute a Question Bank that includes more than 9300 questions neatly organized according to topic. The Question Bank is the perfect tool for busy teachers or new teachers. Even if you don't use the website with your classes, the Question Bank will assist you in quickly putting together quizzes, tests and other documents with high-quality questions that target student's conceptions of physics principles. And if you do use The Physics Classroom website, the Question Bank is the perfect complement to the materials found at the website. (Cost: $25 download)