August 17th, 2016

In this lesson, students look for patterns in their data and as a class compare/come to an agreement about the patterns that exist in the energy of someone swinging.

3.4 — Energy: Swinging – Part III

App Features

Using the energy lens students will:

• Use previously recorded performances.
• Open the graph drawer.
• Add kinetic and potential energy stickers.

Expected Activity Time

• Total Activity Time: 45 minutes
• Introduction: 15 minutes
• Investigation: 20 minutes
• Discussion: 10 minutes

Materials and Prep

• iPad with the Playground Physics app
• Videos created by students in the app
• Worksheet: Energy: Swinging – Part III

Activity

Introduction: 15 minutes

• Tell students that when scientists study the world they look for trends or patterns in natural phenomena. These patterns are things that happen consistently because they are controlled by the physical properties of Earth. Tell students that today they are going to be physicists and look for the patterns in energy.
• Remind students that in the last lesson they learned about kinetic and potential energy. Tell students that they are going to build on those skills by learning about kinetic and potential energy in relation to speed using the graphs that the Playground Physics app creates.
• Project the “Thinking About Graphs” portion of the worksheet and have students follow along on their own copies. This worksheet is intended to help students learn to read the graphs in the app. Work through the worksheet as a class.

Investigation: 20 minutes

• Tell students that they are going to look for patterns in the same video they used in the last lesson. Pass out iPads to groups of students. To access the videos their group recorded initially, students should work in the same group and should use the same iPad as in previous lessons. Use the groups sheet provided in the “Getting Started” section to help keep track of this.
• Have students pull up the video of someone in their group swinging that they used for the last lesson. The path of motion for the person swinging should still be marked on the video so they won’t need to re-annotate the video. Make sure that students have annotated the path of motion for multiple full swings (back and forth). Because the lesson looks for patterns in energy, students will not see this unless they have tracked the path of motion for multiple passes back and forth of the swing in the video.
• Have students open the graph drawer so they can see the graph “along path” of the motion in the video and draw the graph for speed on the space in the worksheet.
• Have students circle the places on the graph where the person was moving the fastest and place a box around the places where the person was moving the slowest.
• The graph of person should be cyclical with the speed increasing and decreasing each time the swings back and forth.
• Have students place kinetic and potential energy stickers in the video. How many stickers are appropriate to place on the video will depend on how many times the person in the video swings back and forth.
• Have students describe what is happening when the person is moving the fastest, what is happening when the person is moving the slowest, when the person is the furthest from the ground, and the overall patterns that exist in the energy in association with the speed of the person who is swinging.
• Have students use their observations to complete the “Patterns in Energy” portion of the worksheet together in their groups.

Discussion: 10 minutes

• Have the class come back together and have each group share the patterns they noted in the investigation.
• If there are discrepancies in the patterns, discuss as a class what could cause the differences groups saw in their patterns. Ask the class if everyone should have the same patterns. Have students share their reasons for why or why not.
• Remember to check the Parking Lot of questions at the end of the class period. Remove any questions that have been answered and add any new questions that may have come up.

1. At this point, the rocket is traveling fast because it was just launched. The rocket still has a high level of kinetic energy as a result of the force of the air that caused the rocket to launch.
2. The potential energy is increasing at this point because the height of the rocket from the ground is increasing.

Patterns in energy

7. Below are some of the overall patterns in the forces on a person jumping rope that your students may notice.
• The potential energy of the person swinging increases as they get further from the ground.
• The potential energy of the person swinging is at a maximum when the person is furthest from the ground.
• Kinetic energy increases as the speed of the swinger increases.
• The kinetic energy of the swinger is at a maximum when the person is moving the fastest. This happens at the bottom or apex of the arch of motion of the swing.

Worksheet Previews

Apps used
Duration: 40-60 mins
Prep: Easy

Big Idea

The purpose of this activity is to provide students experience interpreting the data from the graphs in the Playground Physics app and for them to identify the patterns that exist in the energy of someone swinging.

Learning Objectives

• Students will be able to identify the moments while swinging where the kinetic and potential energy of the swinger is the highest.
• Students will be able to describe how kinetic and potential energy change as someone swings.

NEXT GENERATION SCIENCE STANDARDS
Disciplinary Core Ideas: Forces and Motion
All positions of objects and the directions of forces and motions must be described in an arbitrarily chosen reference frame and arbitrarily chosen units of size. In order to share information with other people, these choices must also be shared.

Crosscutting Concepts: Patterns
Graphs, charts and images can be used to identify patterns in data.

COMMON CORE LEARNING STANDARDS
Key Ideas and Details
CCSS.ELA-LITERACY.RST.6-8.3: Follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks.

NEW YORK INTERMEDIATE SCIENCE STANDARDS
Standard 1: Analysis, Inquiry, and Design
The central purpose of scientific inquiry is to develop explanations of natural phenomena in a continuing, creative process.

Standard 4: The Physical Setting
PS 4.1a: All energy transfers are governed by the law of conservation of energy.

PS 4.1c: Potential energy is the energy an object possesses by virtue of its position or condition.

PS 4.1d: Kinetic energy is the energy an object possesses by virtue of its motion.

Vocabulary

• Speed is how fast an object is moving regardless of its direction.
• Kinetic energy (KE) is the energy of an object in motion.
• Potential energy (PE) is stored energy that an object has as a result of its vertical position.