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Home Concept Builders Vibrations and Waves Vibrating Mass on a Vertical Spring: Velocity and Force Directions

Vibrating Mass on a Vertical Spring: Velocity and Force - Directions

Using the Vertical Springs: Velocity and Force Concept Builder is quite simple. There are three different activities. Each activity has its own unique set of tasks to complete. In the first activity - Speed Anlaysis - you are presented with a diagram of a mass vibrating on a vertical spring with three locations along its back-and-forth path. You must identify where on the path that the speed is the greatest or the smallest and how speed is changing from one location to another. You do so by tapping on one of the four choices (or the radio button to the left of the choice). Tapping highlights your selection by turning the text and the radio button red. You can deselect your choice by tapping a second time or by tapping on a different answer option. Tapping also displays a Check Answer button at the bottom right of the Concept Builder. Once you are satisfied with your answer, tap on the Check Answer button. Your answers will be evaluated and (if you are using a Task Tracker account) your Progress Report will be updated.

In the second activity - Forces Analysis - you are presented with the same diagram of a mass vibrating on a vertical spring with three locations along its back-and-forth path. You must identify where on the path that the net force is the greatest or the smallest and how net force is changing from one location to another. You do so by tapping on one of the four choices (or the radio button to the left of the choice). Tapping highlights your selection by turning the text and the radio button red. You can deselect your choice by tapping a second time or by tapping on a different answer option. Tapping also displays a Check Answer button at the bottom right of the Concept Builder. Once you are satisfied with your answer, tap on the Check Answer button. Your answers will be evaluated and (if you are using a Task Tracker account) your Progress Report will be updated.

In the third activity - Free-Body Diagrams - you are presented with the same diagram of a mass vibrating on a vertical spring with three locations along its back-and-forth path. There are two types of questions in this activity. In one type you must identify the correct free-body diagram for a given location on the path. You select the diagram by tapping on it. When selected, a grey box will surround the selected diagram. Tap a second time to deselect it (if nedded) or tap on a different diagram. As long as you make a selection, a Check Answer button will appear at the bottom of the page. In the second type of question in this activity, you must identify how the magnitude and or the direction of the gravity and the spring force changes as the mass moves from one location to another location. You answer the questions by tapping on a button that toggles through the three or four answer options. Select your two answer options and a Check Answer button will be displayed below the questions. In both types of questions, tap on the Check Answer button when you are satisfied with your answer choice. Your answers will be evaluated and (if you are using a Task Tracker account) your Progress Report will be updated.


You are shown a velocity-time graph representing the mass's back-and-forth motion for two periods. A section of the graph is shaded red. You must match the shaded section to a particular movement of the mass along its path. There are six options to choose from. Tap on the option (or the radio button to the left of the option) to select that option. When selected, the words will turn red and the radio button will show a red dot. Tap a second time to deselect it or tap on a different answer option to select it instead. As long as an answer is selected, a Check Answer button is displayed at the bottom of the window. If you are satisfied with your answer, tap on the Check Answer button. Your answer will be evaluated and your Progress Report will be updated.

Your goal is to earn "Stars" and to complete one or more activities. Stars are earned when you show success on a particular question (displayed on Task Tracker accounts only). Once you show success on all the questions for a particular activity, you will earn the Trophy for that activity.

Concept Builder Teacher Notes