### Notes:

The Getting a Handle on Torque Concept Builder is an adjustable-size file that displays nicely on smart phones, on tablets such as the iPad, on Chromebooks, and on laptops and desktops. The size of the Concept Builder can be scaled to fit the device that it is displayed on. The compatibility with smart phones, iPads, other tablets, and Chromebooks make it a perfect tool for use in a 1:1 classroom.

### Teaching Ideas and Suggestions:

This Concept Builder is intended for use near the early stages of a learning cycle on torque, rotation, and rotational equilibrium. The Concept Builder has four levels of difficulty and progression through each level would provide students with a very good introductory understanding of torque and the rotation it causes when not balanced by an opposing torque. Every question is identical - in which direction does the meter stick rotate. The graphic changes from question to question. Students will quickly recognize that there are two factors that must be considered when thinking about torque - the amount of force exerted on the meter stick and the distance between the fulcurm and where the force is exerted.

This Concept Builder was intended as an in-class activity. It would make a great follow-up to a lab consisting of a similar set-up - meter sticks and hanging masses. After labwork or demonstration and some discussion of torque and how to calculate it, allow students to test their understanding with the use of this Concept Builder. Teachers using the Concept Builder should preview the activity (or view the Questions in the separate file) in order to judge which levels would be most appropriate for their students. Each level of difficulty goes rather quickly so it doesn't hurt to have students complete all four levels or at least the last three levels of difficulty.

In order to complete a level, a student must correctly analyze each situation at that level. If a student's analysis is incorrect, then the student will have to correctly analyze the same or very similar situation twice in order to successfully complete the level. This approach provides the student extra practice on situations for which they exhibited difficulty. As a student progresses through a level, a system of stars and other indicators are used to indicate progress on the level. A star is an indicator of correctly analyzing the situation. Once a star is earned, that situation is removed from the que of situations to be analyzed. Each situation is color-coded with either a yellow or a red box. A red box indicates that the student has incorrectly analyzed the situation and will have to correctly analyze it twice before earning a star. A yellow box is an indicator that the situation must be correctly analyzed one time in order to earn a star. Once every situation at a level has been analyzed, the student earns a medal which is displayed on the Main Menu. This system of stars and medals allows a teacher to easily check-off student progress or offer credit for completing assigned levels.

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.

### Related Resources

As of this writing (August, 2017), there are only a few supporting resources at The Physics Classroom website that serve as complementary supports for the Getting a Handle on Torque Concept Builder. We suspect that this could change over the next few years. Here is what we do have:
• Physics Interactive - Balance Beam
The Balance Beam Interactive in our Physics Interactives section makes for an excellent complementary support for this Concept Builder. The interactive simulation provides students with a virtual set-up of the lab that many teachers do with a meter stick and hanging masses. Students can hang varying masses at various locations and observe whether the meter stick rotates clockwise or counter-clockwise. We believe that the hands-on version of this should be a teacher's first choice if the equipment is readily available. The Interactive is an excellent alternative for those teachers who do not have the equipment required to do the hands-on activity or simply wish to offer a second follow-up experience.

Additional resources and ideas for incorporating Getting a Handle on Torque into an instructional unit on Balance and Rotation  can be found at the Teacher Toolkits section of The Physics Classroom website.  Visit Teacher Toolkits.