This Concept Builder is intended for use in the early to middle stages a learning cycle on energy and energy conservation. There are three highly scaffolded difficulty levels which present numerical information regarding mass and height for as many as 3 locations. Students must use the provided values to determine potential energy (PE) and kinetic energy (KE) values at each of the locations. There is a loss of mechanical energy for each Difficulty Level as the effect of friction and air resistance changes a portion of the energy from mechanical to non-mechanical forms (thermal energy and internal vibrations). The amount of dissipated energy is indentified in the motion description. The computational difficulty is easy to moderate. The concept of energy accounting will become a clear outcome of the activity.

The numerical values in each difficulty level are selected at random from a set of permitted values. It is unlikely that two side-by-side students will have exactly the same problem.  This variation changes the conversation from what is your answer for ... to how do you go about solving for ... .

We recommend all three difficulty levels, beginning with the easiest. Students will quickly gain confidence with manipulating the numerical vaues to determine the PE values. The KE values make up the difference between the PE and the total mechanical energy (TME). Student misses are tracked and use to determine a Health Rating. The Health Rating is published at the completion of the difficulty level. The formula for determining a Health Rating is shown on a separate page. Students can repeat the exercise as many times as needed to improve their grade above a minimum-required level. 

This Concept Builder was intended as an in-class activity or as an assigned out-of-class activity for those classrooms subscribed to Task Tracker. After some lab work, some discussion of how to analyze energy values, and some guided practice, allow students to try it for themselves. Teachers using the Concept Builder with their classes should preview the activity (or view the Questions in a separate file) in order to judge which difficulty levels would be most appropriate for their students.

 

Students can complete as much of the table as they wish before checking their answers. And they can check their answers as many times as they wish. Feedback regarding the correctness of their answers is immediate and provided using a color-coding system. Correct answers are displayed in a table cell with a green background; these correct answers become locked and cannot be changed. Incorrect answers are displayed in a table cell with a red background. Each time students check their answers, the number of missed answers is determined. A running tally is kept of the number of misses. When a student accurately completes the table, a Health rating is displayed on the screen. The Health rating is dependent upon the number of misses. Formulas for computing the Health rating are discussed on a separate page. The Health rating is also displayed on the Main Menu screen for any completed difficulty level. A student can always repeat a difficulty level in order to improve their Health rating for that level. The best Health rating is always displayed on the Main Menu screen below the trophy for that difficulty level.

We leave it to the discretion of individual teachers as to what they wish to do with the Health rating information. We recognize that there will be some teachers who feel most comfortable with their students in simply requiring that a difficulty level be completed and  trophy be earned. Other teachers may wish to require completion of a difficulty level with a minimum Health rating. For instance, such teachers may require that each difficulty level be completed with a 70% or higher Health rating. Still other teachers may tie the Health rating into a grade or allow a homework pass for completing an activity that exceeds a 90% Health rating. Decisions as to what to do with the Health rating are best left for individual teachers who know their students the best.


 

The most valuable (and most overlooked) aspect of this Concept Builder is the Help Me! feature. Each question group is accompanied by a Help page that discusses the specifics of the question. This Help feature transforms the activity from a question-answering activity into a concept-building activity. The student who takes the time to use the Help pages can be transformed from a guesser to a learner and from an unsure student to a confident student. The "meat and potatoes" of the Help pages are in the sections titled "How to Think About This Situation:" Students need to be encouraged by teachers to use the Help Me! button and to read this section of the page. A student that takes time to reflect upon how they are answering the question and how an expert would think about the situation can transform their naivete into expertise. 

 

 

There are numerous resources at The Physics Classroom website that serve as very complementary supports for the Energy Analysis 1 Concept Builder. These include:

Additional resources and ideas for incorporating Energy Analysis 1 into an instructional unit on Work and Energy can be found at the Teacher Toolkits section of The Physics Classroom website.  Visit Teacher Toolkits.