Buoyancy. Frisbee Physics. Teacher s Guide

Transcription

1 Buoyancy Frisbee Physics Teacher s Guide

2 Table of Contents Introduction 3 How to use the CD-ROM 4 Buoyancy Unit Overview and Bibliography 7 Background 8 Video Segments 9 Multimedia Resources 9 Unit Assessment Answer Key 9 Unit Assessment 10 Activity One Sink or Swim 11 Lesson Plan 12 Activity Sheet 14 Activity Two Shape Counts 15 Lesson Plan 16 Activity Sheet 18 Activity Three Transparent Submarine 19 Lesson Plan 20 Activity Sheet 22 Frisbee Physics Unit Overview and Bibliography 23 Background 24 Video Segments 25 Multimedia Resources 25 Unit Assessment Answer Key 25 Unit Assessment 26 Activity One Flying Wing 27 Lesson Plan 28 Activity Sheet 30 Activity Two Fantastic Frisbee Flying 31 Lesson Plan 32 Activity Sheet 34 Activity Three Friction-Friction-Friction 35 Lesson Plan 36 Activity Sheet 38

3 Introduction Welcome to the Newton s Apple Multimedia Collection! Drawing from material shown on public television s Emmy-awardwinning science series, the multimedia collection covers a wide variety of topics in earth and space science, physical science, life science, and health. Each module of the Newton s Apple Multimedia Collection contains a CD-ROM, a printed Teacher s Guide, a video with two Newton s Apple segments and a scientist profile, and a tutorial video. The Teacher s Guide provides three inquiry-based activities for each of the topics, background information, assessment, and a bibliography of additional resources. The CD-ROM holds a wealth of information that you and your students can use to enhance science learning. Here s what you ll find on the CD-ROM:! two full video segments from Newton s Apple! additional visual resources for each of the Newton s Apple topics! background information on each topic! a video profile of a living scientist working in a field related to the Newton s Apple segments! an Adobe Acrobat file containing the teacher s manual along with student reproducibles! UGather and UPresent software that allows you and your students to create multimedia presentations! QuickTime 3.0, QuickTime 3 Pro, and Adobe Acrobat Reader 3.0 installers in case you need to update your current software The Newton s Apple Multimedia Collection is designed to be used by a teacher guiding a class of students. Because the videos on the CD-ROM are intended to be integrated with your instruction, you may find it helpful to connect your computer to a projection system or a monitor that is large enough to be viewed by the entire class. We have included a videotape of the segments so that you can use a VCR if it is more convenient. Although the CD-ROM was designed for teachers, it can also be used by individuals or cooperative groups. With the help of many classroom science teachers, the staff at Newton s Apple has developed a set of lessons, activities, and assessments for each video segment. The content and pedagogy conform with the National Science Education Standards and most state and local curriculum frameworks. This Teacher s Guide presents lessons using an inquirybased approach. If you are an experienced teacher, you will find material that will help you expand your instructional program. If you are new to inquirybased instruction, you will find information that will help you develop successful instructional strategies, consistent with the National Science Education Standards. Whether you are new to inquiry-based instruction or have been using inquiry for years, this guide will help your students succeed in science. WE SUPPORT THE NATIONAL SCIENCE EDUCATION STAND ANDARDS ARDS The National Science Education Standards published by the National Research Council in 1996 help us look at science education in a new light. Students are no longer merely passive receivers of information recorded on a textbook page or handed down by a teacher. The Standards call for students to become active participants in their own learning process, with teachers working as facilitators and coaches. Newton s Apple s goal is to provide you with sound activities that will supplement your curriculum and help you integrate technology into your classroom. The activities have been field tested by a cross section of teachers from around the country. Some of the activities are more basic; other activities are more challenging. We don t expect that every teacher will use every activity. You choose the ones you need for your educational objectives. Educational materials developed under a grant from the National Science Foundation 3

4 Teacher s Guide We suggest you take a few minutes to look through this Teacher s Guide to familiarize yourself with its features. Using the CD-ROM When you run the Newton s Apple CD-ROM, you will find a main menu screen that allows you to choose either of the two Newton s Apple topics or the scientist profile. Simply click on one of the pictures to bring up the menu for that topic. Each lesson follows the same format. The first page provides an overview of the activity, learning objectives, a list of materials, and a glossary of important terms. The next two pages present a lesson plan in three parts: ENGAGE, EXPLORE, and EVALUATE.! ENGAGE presents discussion questions to get the students involved in the topic. Video clips from the Newton s Apple segment are integrated into this section of the lesson.! EXPLORE gives you the information you need to facilitate the student activity. Main Menu Once you have chosen your topic, use the navigation buttons down the left side of the screen to choose the information you want to display.! EVALUATE provides questions for the students to think about following the activity. Many of the activities in the collection are open-ended and provide excellent opportunities for performance assessment. GUIDE ON THE SIDE and TRY THIS are features that provide classroom management tips for the activity and extension activities. Topic Menu The Background button brings up a short essay that reviews the basic science concepts of the topic. This is the same essay that is in the Teacher s Guide. 4 Introduction

5 Playing the Video The Video button allows you to choose several different clips from the video segment. We have selected short video clips to complement active classroom discussions and promote independent thinking and inquiry. Each video begins with a short introduction to the subject that asks several questions. These introductory clips can spark discussion at the beginning of the lesson. The Teacher s Guide for each activity presents specific strategies that will help you engage your students before showing the video. Each of the individual clips are used with the lesson plans for the activities. The lesson plan identifies which clip to play with each activity. Multimedia Tools The Newton s Apple staff has designed a product that is flexible, so that you can use it in many different ways. All of the video clips used in the program are available for you to use outside the program. You may combine them with other resources to create your own multimedia presentations. You will find all the video clips in folders on the CD-ROM. You may use these clips for classroom use only. They may not be repackaged and sold in any form. Video Menu Once you select a video and it loads, you ll see the first frame of the video segment. The video must be started with the arrow at the left end of the scroll bar. As you play the video, you can pause, reverse, or advance to any part of the video with the scroll bar. You can return to the Clips Menu by clicking on the Video button. You will also find a folder for UGather and UPresent. These two pieces of software were developed by the University of Minnesota. They allow you to create and store multimedia presentations. All of the information for installing and using the software can be found in the folder. There is an Adobe Acrobat file that allows you to read or print the entire user s manual for the software. We hope you will use these valuable tools to enhance your teaching. Students may also wish to use the software to create presentations or other projects for the class. Educational materials developed under a grant from the National Science Foundation 5

6 Technical Information Refer to the notes on the CD-ROM case for information concerning system requirements. Directions for installing and running the program are also provided there. Make sure you have the most current versions of QuickTime and Adobe Acrobat Reader installed on your hard drive. The installation programs for QuickTime 3, QuickTime Pro, and Acrobat Reader 3.0 can be found on the CD-ROM. Double-click on the icons and follow the instructions for installation. We recommend installing these applications before running the Newton s Apple Multimedia program. Trouble Shooting There are several Read-Me files on the CD-ROM. The information found there covers most of the problems that you might encounter while using the program. Integrating ting Multimedia We suggest that you have the CD-ROM loaded and the program running before class. Select the video and allow it to load. The video usually loads within a couple of seconds, but we recommend pre-loading it to save time. All of the video segments are captioned in English. The captions appear in a box at the bottom of the video window. You can choose to play the clips in either English or Spanish by clicking one of the buttons at the bottom right of the screen. (You can also choose Spanish or English soundtracks for the scientist profile.) The Resources button provides you with four additional resources. There are additional video clips, charts, graphs, slide shows, and graphics to help you teach the science content of the unit. Resources Menu The other navigation buttons on the left side of the window allow you to go back to the Main Menu or to exit the program. 6 Introduction

7 Buoyancy Teacher s Guide To Float or Not to Float? Why do some objects float while other objects sink? Why does a heavy ship float while a light pebble sinks? Why do ships have differently shaped hulls? What makes humans sink and float? How does a submarine work? Themes and Concepts! density! displacement! models! scale and structure! systems and interactions National Science Education Standards Content Standard A: Students should develop abilities necessary to do scientific inquiry. Content Standard B: Students should develop an understanding of motions and forces. Content Standard E: Students should develop understandings about science and technology. Activities 1. Sink or Swim? approx. 10 min. prep; 45 min. class time Will an object float or sink in water? Students examine the relationship between the weight of an object and the weight of the water it displaces. 2. Shape Counts approx. 15 min. prep; 50 min. class time Objects that sink can sometimes be made to float by altering their shapes. Students conduct experiments to see how the density of a liquid and the shape of an object influence buoyancy. 3. Transparent Submarine approx. 10 min. prep; 40 min. class time How does a submarine sink to the depths of the ocean and then float to the surface? Students make their own submarine and find out. More Information Internet Newton s Apple (The official Newton s Apple web site with information about the show and a searchable database of science ideas and activities.) Boat Safe Kids (Learn about buoyancy, and the different types of hulls that boats have.) How Stuff Works helium.htm (Learn how a hot air balloon works with buoyancy.) Canadian Ballooning Association balloons.htm (Why a hot air balloon rises and a photo with the parts labeled.) SciTech-Floating in Air, Floating in Water aquatic/buoy.html#physics (Buoyancy and fish) Explore Science floatlog.htm (Experiment with a floating log, by changing its mass, length, radius and the water s density.) Internet Search Words buoyancy displacement floating Educational materials developed under a grant from the National Science Foundation 7

8 Buoyancy Books and Articles DeVito, A., and G. H. Krockover. Creative sciencing: Ideas and activities for teachers and children. Boston, MA: Little, Brown and Co., 1980 Williams, B. Ships and other Seacraft. New York, NY: Warwick Press, Willow, D., and E. Curran. Science Sensations. Reading, MA: Addison Wesley, Wong, O. K. Is Science Magic? Chicago, IL: Children s Press, Community Resources Community Resources local university physics department local aquarium local boat club local marine store Background During the third century B.C., a Greek scientist and mathematician named Archimedes made a profound discovery while taking a bath. When he stepped into his bathtub, he noticed how the water spilled over the edge of the tub. He realized this was a clue as to how objects float. His conclusion is known as Archimedes principle: Any object immersed in a liquid is buoyed up by a force equal to the weight of the liquid displaced. Any object whether it sinks or floats is subject to this buoyant force. As Archimedes discovered, buoyant force the total upward force a liquid exerts on an object immersed in that liquid is also what allows objects to float. If an object weighs the same or less than the buoyant force, the object will float. If the object weighs more than the buoyant force, the object will sink. This discovery allowed Archimedes to solve a challenge posed by the Greek ruler King Hiero II. The king asked Archimedes to determine whether a certain crown was made of pure gold or of a gold and silver alloy. Archimedes took two lumps of metal, one of gold and one of silver, each of which had the same weight as the crown. Then he filled a large vessel with water, dropped in the lump of silver, and measured the weight of water that ran over the side. After this, he did the same thing with the lump of gold, and found that less water was displaced by the gold than by the silver. When Archimedes tested the king s crown in the same manner, he discovered that the crown displaced more water than the gold, but less than the silver. Thus he was able to prove to King Hiero that the crown was indeed an alloy that contained both gold and silver. Buoyancy also depends on an object s shape. Very dense objects may float if their shapes are modified, allowing their weight to displace a larger volume of liquid. Will a 10,000-kg (an 11-ton) block of steel sink? Most definitely. The weight of the water displaced by the block is less than the block s weight. Then what about a ship weighing 10,000 kg (11 tons)? Won t it sink too? No. Adding hollow open spaces in the hull allows the ship to displace a volume of water equal in weight to the ship. Archimedes principle also states that when an object sinks, the apparent weight loss of the object is equal to the weight of the displaced water. This helps explain why objects underwater seem to be lighter. 8 Buoyancy

9 Video & Stills Video Clip 1 00:52 to 01:24 David Heil learns about the concept of displacement. (33 sec.) Video Clip 2 01:24 to 2:21 Jack Netland weighs in on displacement, and David Heil learns the physics of buoyancy. (56 sec) Video Segments Introduction 00:00 to 00:40 David Heil asks some questions about buoyancy. (41 sec.) Additional Resources Button A Illustration: How weight effects the buoyancy Video Clip 3 02:22 to 04:47 David Heil discovers that even a chunk of lead can float. The secret is in the shape. (2 min. 23 sec.) Video Clip 4 04:53 to 06:33 David Heil becomes a human submarine and learns that by changing his volume he can sink or swim. (1 min. 37 sec.) Button C Video: Newton s Apple Science Try It - Submariner Button B Video: Newton s Apple Science Try It: Helium Balloon Button D Video: Newton s Apple Science Try It - Density Stacker Unit Assessment Answer Key The Unit Assessment on the following page covers the basic concepts presented in the video segment and the background on the Unit Theme section in this guide. The assessment does not require completing all of the activities. The Unit Assessment may be used as a pre- or post-test. However, students should view the complete Newton s Apple video before doing this assessment. There is additional assessment at the end of each activity. Think about it 1. It would be possible that one or both could float or sink, depending on the shape of the piece of lead. If the lead is boat-shaped and displaces enough water, the lead would float. If the lead is a solid chunk or does not displace enough water, it will sink. 2. The toy boat displaces more water, because it must displace enough to achieve buoyancy. Since the two objects have the same weight, the boat would definitely displace more water. 3. The shape of the object can greatly affect its volume. An object shaped like a boat s hull or a sphere that is hollow inside can displace more fluid and is more likely to float. A solid block of metal or a pipe that is open at both ends does not displace as much fluid and therefore is not buoyant. 4. Yes. For example, a ball could be filled with water and not be buoyant. The same ball could be filled with air and maintain buoyancy. (Examples will vary.) 5. A life jacket is filled with material that is much less dense than water. The material is very buoyant. When worn, the buoyant life jacket increases a person s total volume by enough to keep the person afloat. What would you say? 6. a 7. c 8. c 9. b 10. d Educational materials developed under a grant from the National Science Foundation 9

10 Unit Assessment What do you know about Buoyancy? Write the answers to these questions in your journal or on a separate piece of paper. Think about it 1. If you had two pieces of lead, both of which weighed the same, could it be possible that one would sink and one would float? Explain. 2. Which object displaces more water, a 2 kg rock sinking to the bottom or a 2 kg toy boat floating on the surface? Explain your answer. 3. What does shape have to do with buoyancy? 4. Can you change the buoyancy of an object without changing its shape? Explain. 5. How does a life jacket keep a person afloat? What would you say? 6. In order to float, an object must displace an amount of water equal to or greater than a. the object s weight. b. the object s volume. c. one-half the object s weight. d. two-thirds the object s volume. 7. An object s buoyancy is determined by a. the force of the object pressing down on the water. b. an object s natural tendency to float. c. the force of the water pushing up against the object. d. the object s weight. 8. What is the most important factor determining an object s buoyancy? a. how much it weighs b. how large it is c. how much water it displaces d. how it is shaped 9. If a man floating in the water blew all of the air out of his lungs, what would happen? a. He would continue to float. b. It would decrease his total volume, and he would probably sink. c. It would depend on how much he weighs. d. none of the above 10. A log and a metal pipe weigh the same. The log floats, but the pipe sinks. Why? a. The log may be less dense than the pipe. b. The log may have a greater volume than the pipe. c. The pipe displaces less water than the log. d. all of the above Copyright Twin Cities Public Television & GPN. Permission granted to reproduce for classroom use. 10 Buoyancy

11 Activity 1 Sink or Swim? Why do some objects float in water, while other objects sink? If you step in a bucket filled with water, why does the water spill out? Getting Ready Overview A small pebble sinks in water, yet a heavy, steel ship floats. In this activity, students explore how the weight of an object and the weight of the water it displaces are related. They experiment with objects of various shapes and weights to see why some objects sink and others float in water. They measure the weight of several objects and the weight of the water these objects displace when placed in the water. By comparing these weights for sinking and floating objects, students draw conclusions as to why objects sink or float. Important Terms buoyancy principle The upward force exerted by a fluid on an object equal to the weight of the fluid displaced. displacement The pushing aside of fluid when an object is placed in it. Objectives After completing this activity, students will be able to! define displacement and the principle of buoyancy (Archimedes principle)! explain in their own words why some objects sink and other objects float! and, predict whether an object will float when given its weight and the weight of the liquid it displaces Time Needed Preparation: approximately 10 minutes Classroom: approximately 45 minutes Materials For the teacher:! scales! 2 beakers with spouts! an apple! small stone that weighs less than the apple! 2 cups water For each group of students:! scales! variety of interesting objects, some of which sink, others that float (e.g., lead weights, a golf ball, a tennis ball, an orange, etc.)! 2 beakers with spouts! 2 cups water! paper towels or sponge for cleaning up Educational materials developed under a grant from the National Science Foundation 11

12 Buoyancy Video Clip 1 00:52 to 01:24 David Heil learns about the concept of displacement. (33 sec.) Video Clip 2 01:24 to 02:21 Jack Netland weighs in on displacement, and David Heil learns the physics of buoyancy. (56 sec) Guide on the Side! You may wish to begin the lesson by viewing the Introduction from the Video Menu on the CD-ROM [00.00 to 00.40]. Find out what students already know buoyancy by discussing the questions posed by David Heil.! If beakers are not available, milk cartons or jars may be used to construct substitutes.! Make sure students understand the difference between the mass of an object and the volume of the object. These concepts are important in the understanding of displacement and buoyancy.! You may want to have students bring in various objects from home that can be used in this activity. However, don t tell students what they are going to use the object for.! If it is appropriate, you may wish to view the entire Newton s Apple segment on buoyancy after completing the activity. Preparation Here s How! Set up the computer to play the CD-ROM (or set up the VCR and cue tape).! Gather the materials for each team of students.! Make a copy of Activity Sheet 1 for each student.! Review the Background information on page 8. Engage (Approx. 10 min.) Fill two beakers with water until the water nearly spills out of the spouts. Place the empty cups under the spouts to catch the displaced water. Show students the apple and the small (lighter) stone. Weigh the apple and the stone. Have a volunteer record the weights on the board. Ask students to predict what will happen when you place them in the beakers. Accept all answers. Then show the students what happens when you carefully place the stone into one beaker and the apple into the second beaker. Ask why the heavier apple floats while the lighter stone sinks. For that matter, why does a heavy steel ship float, while a small pebble sinks? You may want to list student responses on the board. (Accept all answers.) Tell the students that the answer to these questions is given in the video they will see. Show Video Clip 1 [00:52 to 01:24]. Briefly discuss the video to make sure students understand the buoyancy principle. Then show Video Clip 2 [01:24 to 02:21], which deals with displacement. Tell students that they are going to explore the principles of buoyancy and displacement by experimenting with several objects to determine if they will float or sink. Explore (Approx. 35 min.) Students should work in teams of three or four. Before students begin their experiments, repeat the demonstration with the apple and the stone, showing students how to record the data. As a whole class, establish the weight of the cup and explain how this amount will need to be subtracted from each water weight. Build this into the chart for some simple math equations. After the teams have conducted their experiments and recorded their data, ask each team what rule they came up with for predicting whether an object will sink or float. (Note: There may have been some variation in the weight of objects and displaced water due to measurement error. If there are discrepancies, repeat the measurements.) 12 Buoyancy

13 Activity 1 Evaluate 1. When an object is placed into a tub filled to the top with water, water is forced to flow out of the tub. Will more water flow out of the tub if the object floats or if it sinks? Explain your answer. (More will flow out if the object floats, because to float it must displace water.) 2. If an object weighing 250 grams displaces 150 grams of water, will it sink or float? Explain your answer using the buoyancy principle. (The buoyancy principle states that the upward force on the object will equal the weight of the water the object displaces. In this case, since the upward force is less than the weight of the object, the object will sink.) 3. Canoes have relatively flat bottoms and do not sink very far into the water unless they are very heavily loaded. For this problem, assume that a canoe weighs 50 kg and the cargo weighs another 50 kg. Is the canoe likely to displace more than 100 kg of water, less than 100 kg of water, or exactly 100 kg of water? Explain your answer. (Exactly 100 kg of water will be displaced. That will create the upward force necessary to float the canoe and its cargo.) Try This Float the apple again, collect the displaced water and mark how much of the apple was submerged. Cut off the portion of the apple that was above the water. Weigh the submerged portion of the apple and the displaced water. How are the weights related? What portion of the apple had to be submerged in order to displace the entire apple s weight in water? Discuss the findings. Would this ratio be the same for other objects? If you have a spring scale, investigate the apparent weight loss of objects submerged in water. Suspend objects from the scale both in and out of the water and discuss the results. Explore the effect with other fluids of different densities. Archimedes was an ancient Greek mathematician and scientist. The story of his discovery of the relationship between buoyant force and water displacement is fascinating. Research Archimedes and how he discovered the buoyancy principle and how he determined whether the king s crown was made of gold or an alloy. Develop a skit about Archimedes discovery and present it to the class. Educational materials developed under a grant from the National Science Foundation 13

14 Sink or Swim? Activity Sheet 1 Name Class period What you re going to do You re going to determine how an object s weight relates to the amount of water it displaces. How to do it 1. Work with your group. Decide on five or six objects that you are going to test. 2. Predict whether you think the object will float or sink, and record your prediction. 3. Use the method your teacher used with the apple and the rock. Measure the weight of the object and the weight of the water don t forget to figure in the weight of the cup when calculating the weight of the water. Place the object in the cup and then measure the weight of the displaced water. 4. Compare your prediction with what actually happened. 5. Examine the data for the objects that sink. How does the weight of the object compare to the weight of the displaced water? 6. Examine the data for the objects that float. How does the weight of the object compare to the weight of the displaced water? Recording your data ta Make a table in your journal with columns set up like the one below. Object Wt. of object Wt. of water in cup Wt. of cup only Wt. of displaced water Sinks or floats? (total weight) (weight of cup) = (weight of displaced water) What did you find out? What did you find out? What conclusions can you draw about the weight of water displaced by objects that float? What conclusions can you draw about the weight of water displaced by objects that sink? What generalization can you draw from your conclusions? Compare your results with other groups. Do they match? What might have caused any differences? 14 Buoyancy Copyright Twin Cities Public Television & GPN. Permission granted to reproduce for classroom use.

15 Activity 2 Shape Counts Why does a 12-ton block of solid steel sink, while a 12-ton ship floats? How do differently shaped hulls of various boats affect such things as stability, cargo capacity and speed? Getting Ready Overview Students discover how the shape of an object affects whether or not it will float. Students first design and then test different clay shapes to see if they will float. Students explore how the shape of the hull can affect things such as stability, cargo capacity and speed. Objectives After completing this activity, the student will be able to! explain how altering the shape of an object that sinks can make it float! explain how differently shaped hulls affect the performances of boats! predict why a given boat or ship has a particular hull shape Important Terms displacement The pushing aside of fluid when an object is placed in it. hull The hollow, lowermost portion of a boat or ship. keel The central structure in the bottom of the hull that extends from the front to the back of the boat or ship capsize To overturn a boat or ship. Time Needed Preparation: Approx. 15 min. Classroom: Approx. 50 min. Materials For the teacher:! ball of non-drying modeling clay! large, transparent tub of water! paper towels or sponges for cleaning up! pictures of different boats and ships Each team of students:! ball of non-drying modeling clay for each student a tub of water for each team! two identically sized balls of nondrying modeling clay! a tub of water! marbles! spoons Educational materials developed under a grant from the National Science Foundation 15

16 Buoyancy Video Clip 3 02:22 to 04:47 David Heil discovers that even a chunk of lead can float. The secret is in the shape. (2 min. 23 sec.) Guide on the Side! You may wish to begin the lesson by viewing the Introduction from the Video Menu on the CD-ROM [00:00 to 00:40]. Find out what students already know about buoyancy by discussing the questions posed by David Heil.! If students haven t already done Activity 1, you may wish to spend some time discussing the concepts of displacement and buoyancy before beginning this activity.! As always, it is a good idea for you to work through the activity before using it with your students.! If it is appropriate, you may wish to view the entire Newton s Apple segment on buoyancy after completing the activity. Preparation Here s How! Set up the computer to play the CD-ROM (or set up the VCR and cue tape).! Gather the materials for each team of students.! Make a copy of Activity Sheet 2 for each student.! Review the Background information on page 8. Engage (Approx. 20 min.) Organize students into groups of four and give each student a piece of clay. Provide each team with a tub of water. Ask them, Will this piece of clay sink or float in a tub of water? Have them test their predictions by placing their pieces of clay into the tub of water. Distribute copies of Activity Sheet 2. Tell students to work through Part 1 of the sheet. Instruct students to alter the shape of the clay so that it will float. After using their balls of clay to make boats that will float, have students take turns testing their designs. Have the teams share their designs and talk about which designs floated. Ask students why boat-shaped designs worked best. (Accept all answers.) Show Video Clip 3 [02:22 to 04:47]. Discuss how the concept of displacement applies to students clay boats similarly to the piece of lead in the video. Explore (Approx. 30 min.) Tell groups that they will be working with Part 2 of the activity sheet. Distribute two identically shaped balls of clay to each team of students. Challenge students to design a clay boat that is highly stable and that will hold a lot of cargo. Allow groups to look at pictures of various types of ships and speculate about the conditions in which each design would function best. Tell them to follow the instructions on the Activity Sheet. Have students design differently shaped hulls out of their clay and then conduct experiments with their hulls to test the features of the designs. After all groups have completed their experiments, have them share their findings and discuss these questions: Why do you think various boats and ships are designed differently? Which features of each boat design allow that boat to navigate different waters? Encourage students to use their data about the amount of cargo each shape was able to hold, and how easy or difficult each shape was to capsize. What other factors do you think engineers must take into account when designing a boat? 16 Buoyancy

17 Activity 2 Evaluate 1. Using a drinking glass and a tub of water, demonstrate how the shape of an object pushing against the water will influence whether the object floats or sinks. Before placing the mug in the water for each demonstration, predict whether it will sink or float. Explain your reasoning. Demonstration 1: Place the glass in the water bottom first. Demonstration 2: Turn the glass on its side and place it in the water. 2. Some boats have flat bottoms; others have hulls that cut deep into the water. Explain the factors that influence the shape of a boat s hull. (Answers will vary, but should mention how the purpose of the boat is related to design factors such as stability, cargo capacity, and speed.) 3. Given a glass paperweight and a glass jar of the same weight, predict whether each will float or sink. Explain your reasoning. (Answers will vary, but should include that the glass paperweight sinks because its weight is greater than the weight of the water it displaces. The glass jar floats because its shape allows it to sink into the water until it displaces a volume of water equal to its weight.) Try This Choose a type of modern boat or ship to research, and present a report about the engineering and design considerations for the hull. What factors influence the shape of a hull? What factors influence the choices of construction materials? Why are some ships made of wood? Steel? Fiberglass? Research historic sailing vessels from Greek and Roman times through the 1800s. How did the design of sailing ships change over the years? How did the ships designs reflect their purpose merchant, military, exploration? Report your findings to the class. Research the various ways technology is improving the design of boats. Do engineers change the materials used in ship design to account for varying liquid densities or other environmental conditions? Find out whether water temperature affects boat design. Educational materials developed under a grant from the National Science Foundation 17

18 Activity Sheet 2 Shape Counts Name Class Period How to do it Part 1: Why does a 12-ton block of steel sink, while a 12-ton steel ship floats? Using a ball of clay, create an object that floats. Predict which of your teammates designs will float, and then test out your predictions by placing the designs in a tub of water. Take notes on which designs float (or don t!). Designer s name Prediction Sinks or floats? Test result Part 2: Why do ships have differently shaped hulls? Take two balls of clay of the same size. With one ball, create a model boat similar to an ocean liner. With the second ball, create a model boat similar to a barge. Try to keep the thickness of the two hulls the same. Place the ocean liner carefully in a tub of water. Put as many marbles as you can into the ocean liner until it sinks. How many marbles did the ocean liner hold? Repeat this experiment with the barge model. How many marbles did the barge hold? Place the empty ocean liner back in the tub of water. Make waves with a spoon or your fingers so that the model rocks back and forth. Repeat with the barge. Which ship is easier to capsize? Why do you think an ocean liner and a barge have different shapes? Base your answers on the amount of cargo they each hold and how easy they are to capsize. Ocean Liner Barge Cargo Capacity (# of Marbles) Capsizing-test notes 18 Buoyancy Copyright Twin Cities Public Television & GPN. Permission granted to reproduce for classroom use.

19 Activity 3 Transparent Submarine What makes a human sink or float? What makes a submarine sink or float? How does the weight of the water displaced by an object affect whether that object will sink or float? Getting Ready Overview In this activity, students explore two different methods for making an object alternately sink and float. Students build model submarines that will float, sink and float again as they are modified. Objectives After completing this activity, students will be able to! explain how a human can sink or float! demonstrate how a submarine can sink, float, or maintain a steady depth Important Terms buoyancy the tendency of a body to float or to rise when submerged in a fluid submerge to sink below the surface of water or any other enveloping medium Time Needed Preparation: Approx. 15 minutes Classroom: Approx. 40 minutes Materials For the teacher:! 2 identically sized balls of non drying modeling clay! a large transparent tub of water! paper towels or sponges for cleaning up For each team of student:! small (12 oz. to 20 oz.) plastic soft-drink bottle with a screw-on lid! 2 plastic drinking straws! scissors or a screwdriver! marbles (enough to fill the bottle half-way)! small amount of modeling clay! tub of water! paper towels or sponges for cleaning up Educational materials developed under a grant from the National Science Foundation 19

20 Buoyancy Video Clip 4 04:53 to 06:33 David Heil becomes a human submarine and learns that by changing his volume he can sink or swim. (1 min. 37 sec.) Guide on the Side! You may wish to begin the lesson by viewing the Introduction from the Video Menu on the CD-ROM [00:00 to 00:40]. Find out what students already know buoyancy by discussing the questions posed by David Heil.! Remind students to follow established classroom safety procedures when cutting holes in the bottles.! The clay must completely seal the openings around the straws.! You may want to expand this experiment by having students quantify their observations and data. For example, they might measure the weight of the water in the bottle at different points submarine floating, submarine partially submerged, submarine submerged and at equilibrium, and sub on the bottom. Students can work with this data and use it to help them reach conclusions about the sub s buoyancy.! As always, it is a good idea for you to work through the activity before using it with your students.! If it is appropriate, you may wish to view the entire Newton s Apple segment on buoyancy after completing the activity. Preparation Here s How! Set up the computer to play the CD-ROM (or set up the VCR and cue tape).! Gather the materials for each team of students.! Make a copy of Activity Sheet 3 for each student.! Review the Background information on page 8. Engage (Approx. 30 min.) Begin with a brief discussion about how the shape of an object may affect its ability to float, and a demonstration of how altering an object s shape will allow it to float. Show students two identically sized balls of clay. Demonstrate that they sink in water. Ask, How could we alter the clay to make it float? Change one ball into a boat-like shape and demonstrate that it floats. Discuss why. (If you have already done Activity 2, use this demonstration as a review of that experiment.) Ask students if they sink or float in water. Ask them to explain why they sink or float. (Accept all answers.) Play Video Clip 4 [04:53 to 06:33] on sinking or floating in water. Discuss why David Heil was able to float and then sink. (As David inhaled his total body volume expanded until he displaced a weight of water equal to his own weight, so he floated. When he exhaled, he contracted and displaced a weight of water less than his weight, so he sank.) Ask students for examples of other objects that can alternately sink or float. What do they think causes a submarine to float? What causes it to sink? Tell students that they will make a model submarine and investigate for themselves what causes it to float and sink. Explore (Approx. 30 min. over two days) Organize the class into groups and distribute Activity Sheet 3. As your students experiment with the submarines, ask the teams how they think the weight of the submarine compares to the weight of the liquid it is displacing as the submarine floats, sinks and floats again. After clean-up, discuss groups observations. 20 Buoyancy

21 Activity 3 Evaluate 1. In the video, David was able to make himself float by holding his breath, and then sink by blowing all of the air out of his lungs. Explain why this worked. If he were wearing a life vest, would he be able to sink by blowing the air from his lungs? Explain your answer by describing how a life vest helps keep a person afloat. (David decreased his volume by releasing the air from his lungs, therefore he didn t displace as much water and sank. Blowing air out while wearing a life vest would have no effect. The life vest is displacing the water, not the person.) 2. How does a submarine use the buoyancy principle to influence whether it floats to the surface or sinks to the depths? (A submarine changes weight by taking in or discharging water. As water is taken in, the weight of the water combines with the submarine s weight, and the submarine submerges. As the water is discharged, the submarine s weight decreases, and its buoyancy increases.) 3. Explain why a 450-ml can of fried onions floats while a 450-ml can of creamed corn sinks. (The size of the can refers to its capacity [volume], not its weight. The displacement of the heavier can was not enough to create the buoyant force needed to make it float.) Try This Research the construction of a submarine. How heavy is a submarine when it floats? What does the inside of a submarine look like? How does the submarine take on water to make itself heavier? How does it expel this water? Present your answers to the class. Fill a plastic tub with water, place a 12- ounce can of regular cola into the water and observe the results. Then add a 12- ounce can of diet cola into the same tub. Explain the results and report your findings to the class. Research the history of submarines. When and where were the first ones built and used? What were they used for? When did submarines become a part of the modern navy? Prepare an oral report and present it to the class. Educational materials developed under a grant from the National Science Foundation 21

22 Activity Sheet 3 Transparent Submarine Name Class Period What you re going to do You are going to build a submarine and explore the question What makes a submarine sink or float? How to do it Work with your group. 1. Fill a small plastic soft-drink bottle about half-way with marbles and screw the lid on tightly. Tilt the bottle on its side. 2. Using scissors or a screwdriver, carefully poke a hole in the shoulder of the bottle and insert a short piece of a drinking straw approximately 5 cm (2 inches) long. This is the intake. 3. Using scissors or screwdriver, carefully poke a hole on the opposite side of the bottle, a few inches from the bottom of the bottle. Into this hole, insert a long piece of a drinking straw. 4. Use clay to completely seal any openings around the straws. 5. While gently holding the long straw above the water, place the bottle in the water, submerging the short straw. (You need enough marbles in your submarine to hold the intake hole below the surface of the water.) Allow the short straw to fill with water. If necessary, suck on the long straw to draw water into the bottle. Experiment with the sub, allowing it to fill with water and using the long straw to force air into the sub. Recording your data Write down your procedures and observations in your journal. You may want to make sketches of the submarine at different points of buoyancy. What t did you find out? As the submarine fills with water, what happens? If you cover the end of the long straw with your finger, what happens? What makes your submarine surface? What makes your submarine sink? Compare your results with other groups 22 Buoyancy Copyright Twin Cities Public Television & GPN. Permission granted to reproduce for classroom use.

23 Put a Spin on It How do Frisbees fly? How do you throw a Frisbee to get the best results? Why do some people put lubricants on the undersides of their Frisbees? Can a Frisbee fly without spinning? Frisbee Physics Teacher s Guide Themes and Concepts! aerodynamics! airfoils! stability! angular momentum and spinning! models! systems and interactions National Science Education Standards Content Standard A: Students should develop abilities necessary to do scientific inquiry. Content Standard B: Students should develop an understanding of motions and forces. Content Standard E: Students should develop understandings about science and technology. Activities 1. Flying Wing Approx. 10 min. prep; 70 min. classtime Aerodynamics, the science of flying objects, helps explain how Frisbees fly. Build and fly an airfoil and learn how shape and design affect an object s ability to fly. 2. Fantastic Frisbee Flying Approx. 15 min. prep; 60 min. classtime There are many ways to throw a Frisbee. Try a variety of throws and graph the results to discover which techniques are best for accuracy, time aloft and distance. 3. Friction, Friction, Friction Approx. 20 min. prep; 50 min. classtime Why do Frisbee athletes lubricate their Frisbees and wear fake fingernails when competing in freestyle events? Explore the effects of friction. More Information Internet Newton s Apple (The official Newton s Apple web site with information about the show and a searchable database of science ideas and activities.) The SDGO Guide to Flying Disc Sports - Stockholm Disc Golf Open engelska/frisbee/frisbee.htm (This site contains rules for all sorts of flying disc sports, links to world competition, photos, and history.) Ultimate Players Association (Learn all about the sport of ultimate.) Freestyle Players Association (Learn all about the sport of freestyle Frisbee) Disc Golf Webring web_ring.html (A great starting point for any questions you may have about disc golf.) Goaltimate (Learn about the newest Frisbee team sport Goaltimate.) Internet Search Words Frisbee flying disc Frisbee golf Ultimate Frisbee Freestyle Frisbee Educational materials developed under a grant from the National Science Foundation 23

24 Frisbee Physics Books and Articles Malafronte, Victor A., F. Davis Johnson, and Rachel Forbes. The Complete Book of Frisbee : The History of the Sport & the First Official Price Guide. Alameda, CA: American Trends Publishing Co., 1998 Johnson, S.E.D. Frisbee: A practitioner s manual and definitive treatise. New York, NY: Workman Publishing Co., 1975 Additional Information Experimental Aircraft Association EAA Aviation Center Oshkosh,, WI (414) International Frisbee Disc Association P.O. Box 970-P San Gabriel, CA Wham-O Sports Promotion P.O. Box 4 San Gabriel, CA (818) Background At least 2,000 years ago, ancient Greeks first organized discus-throwing competitions. The Frisbee is a modern descendant of that ancient sport. In the late 1800s, as the story goes, Ivy League students ate pies baked by the Frisbie Company, so-called Frisbie pies. Students soon noticed that the pie tins made excellent throwing devices. At the end of World War II, the sport of flying discs began to gain popularity. Around that time, Walter Frederick Morrison experimented with flying discs. He used a revolutionary new material developed during the war by the Eastman Kodak Company plastic. Morrison s first plastic disc flew very well and was much easier to catch than the earlier metal discs. Its one limitation was that the plastic, if not kept warm, would shatter on impact. Despite this apparently fatal flaw, Wham-O, a toy company, bought the rights to the disc from Morrison in Two years later, the first plastic Frisbees went into production. Several scientific factors contribute to the flight of a Frisbee. Its shape allows air to flow smoothly over its surface, reducing the air resistance or drag force. The smooth airflow generates a lift force that keeps the Frisbee airborne. The speed of the air flowing over the curved surface of the Frisbee produces a lower pressure on the top than there is underneath (a result known as the Bernoulli effect). This pressure difference contributes to the lift force. Throwing the Frisbee so it is tilted slightly upward creating a positive angle of attack also contributes to lift. As the tilted Frisbee moves forward through the air, it pushes the air downward. The air, in turn, pushes upward on the Frisbee (as described in Newton s third law of motion). The soaring flight of the Frisbee is a combination of these several effects. Of course, spinning the Frisbee also helps it stay in the air. It is more difficult to change the orientation of a spinning object than a non-spinning object. For example, a top or gyroscope that is not spinning falls down immediately, whereas a spinning top or gyroscope stays upright. In the same way, spinning the Frisbee maintains its stability so the air can flow smoothly over its surface and keep the Frisbee airborne. After you ve learned about the physics of Frisbees, go outside and take one for a spin! 24 Frisbee Physics

25 Video & Stills Video Clip 1 00:42 to 01:46 David Heil s hand gets a lift as he learns about flight and the angle of attack. (1 min. 4 sec.) Video Clip 2 01:47 to 03:03 Jay Shelton shows David Heil that Frisbees need spin as well as lift to maintain a long flight. (1 min. 16 sec.) Video Segments Introduction 00:00 to 00:30 David Heil wants to discover what pizzas and Frisbees have in common. (30 sec.) Additional Resources Button A Slide Show: Comparing different flying discs. Video Clip 3 03:03 to 04:17 David Heil and Jay Shelton use different angles of spin to change a Frisbee s flight path. (1 min. 14 sec.) Video Clip 4 05:02 to 06:36 David Heil learns the physics behind some high-preformance Frisbee stunts. Button C Video: Newton s Apple Science Try It Gyro LP Button B Chart: World s flying disc records Button D Video: Host Peggy Knapp talks about how a stone can skip across the water. Unit Assessment Answer Key The Unit Assessment on the following page covers the basic concepts presented in the video segment and the background on the Unit Theme section in this guide. The assessment does not require completing all of the activities. The Unit Assessment may be used as a pre- or post-test. However, students should view the complete Newton s Apple video before doing this assessment. There is additional assessment at the end of each activity. 1. The Frisbee must be spinning and it must have a positive angle of attack. 2. You could throw it straight up or you could throw it at a very steep angle (especially into the wind). 3. The Frisbee s profile is an airfoil. Air flows over it and generates lift. The circular shape of the Frisbee allows it to spin and maintain stability through the air. 4. Both a Frisbee and a top employ gyroscopic action. They spin to maintain a stable position. When they stop spinning, they lose stability and fall. 5. It needs to be shaped like an airfoil and must have a positive angle of attack. What would you say? 6. c 7. d a 10. a Educational materials developed under a grant from the National Science Foundation 25

26 Unit Assessment What do you know about Frisbees? Write the answers to these questions in your journal or on a separate piece of paper. Think about it 1. What two things are necessary for a Frisbee to achieve a long flight? 2. If you wanted a Frisbee to come back to you like a boomerang, how would you throw it? 3. How does the Frisbee s shape help it fly? 4. How are a Frisbee and a gyroscope similar? 5. What is necessary for a Frisbee to have lift? What would you say? 6. Which of the following Frisbees would probably fly the farthest? a. The Frisbee that is thrown the hardest. b. The Frisbee that is slightly tipped up in front. c. The Frisbee that has the fastest spin. d. The Frisbee that is completely parallel to the ground. 7. The first Frisbees were made out of. a. metal b. wood c. rubber d. plastic 8. Why doesn t a Frisbee flip end-over-end when it is thrown? a. It is shaped like an airfoil. b. It is spinning. c. It has a positive angle of attack d. It has lift. 26 Frisbee Physics 9. The Frisbee is a modern descendent of the ancient discus. a. Greek b. Roman c. Chinese d. Celtic 10. What slows the Frisbee and prevents it from flying further through the air? a. friction b. gravity c. angular momentum d. centripetal force Copyright Twin Cities Public Television & GPN. Permission granted to reproduce for classroom use.

27 Activity 1 Flying Wing What do birds, planes, and spinning plastic discs have in common? How does a Frisbee fly? Why is a Frisbee shaped the way it is? What effect does the shape of an object s surface have on its flight? Getting Ready Overview Students investigate airfoils by comparing what happens when objects of various shapes are thrown into the air. Students discover that certain shapes perform better than others. Students build and fly an airfoil modeled after some commonly found airfoils. Objectives After completing this activity, students will be able to! describe the shape of an airfoil! explain how the shape and tilt of an airfoil like the Frisbee help it fly! build and fly an airfoil. Important Terms airfoil An object, such as an airplane wing or a Frisbee, whose design helps lift it and control its flight through the air. angle of attack The angle between the plane of an airfoil and the horizontal plane. lift The upward force exerted by air on an airfoil. drag Air resistance or the force of the air opposing the motion of the airfoil. Time Needed Preparation: Approx. 15 min. Classroom: approximately 70 minutes Materials For the teacher:! various rectangular shaped objects (e.g., a ruler, a tablet, a book, etc.)! disc-shaped objects similar to a Frisbee (e.g., pie tins, plastic or heavy duty paper plates, lids to round plastic containers, etc.)! examples of airfoils (e.g., toy airplanes, Styrofoam gliders, boomerangs, etc.) For each team of students:! foam meat-packing or deli tray! scissors! emery paper, emery boards, or sandpaper! masking tape! paper clip! stopwatch or a watch with a second hand Educational materials developed under a grant from the National Science Foundation 27

28 Frisbee Physics Video Clip 1 00:42 to 01:46 David Heil s hand gets some lift from as he learns about flight and the angle of attack. (1 min. 4 sec.) Guide on the Side! You may wish to begin the lesson by viewing the Introduction from the Video Menu on the CD-ROM [00:00 to 00:30]. Find out what students already know Frisbee physics by discussing the questions posed by David Heil.! This is a fairly open-ended activity. Encourage students to experiment with different designs and ways of launching their flying wings. You may need to help some groups by asking questions that will help them focus their experiments.! You may wish to enlarge the airfoil illustration from Activity Sheet 1 and trace it onto paper. If students are using foam trays as their construction material, make a template out of paper and place it in the tray so that the upturned tray sides automatically serve as the wing tips. Use sandpaper, emery boards, emery paper or scissors to form and smooth the edges. This will result in a smoother flight. Balance the model by taping a paper clip to the center of the underside of the leading edge.! Flying Hints: If the model dives, bend the trailing edges upward. If the model swoops upward and stalls, bend the trailing edges downward. If the model moves clumsily, it may be tail heavy. Try adding a small weight to the nose. Bending one trailing edge up or down more than the other will correct or cause a turn.! Arrange to have students test their airfoils outside or in a large open room.! As always, it is a good idea for you to work through the activity before using it with your students. Preparation Here s How! Set up the computer to play the CD-ROM (or set up the VCR and cue tape)! Gather the materials for each team of students.! Make a copy of Activity Sheet 1 for each student.! Review the Background information on page 24. Engage (Approx. 20 min.) Begin the activity in a hallway, gym, or other open area. Take various rectangular shaped objects (e.g., a ruler, a tablet) and try to make them glide through the air. Throw them, push them, spin them. Ask students for their observations about how well these objects fly. Next, show students a set of objects that have disc-like shapes that are similar to a Frisbee (e.g., a pie tin, a plastic or heavy-duty paper plate, a lid to a round plastic container) and demonstrate their flying abilities. Again, throw, push and spin them. Ask students for their observations. Encourage students to explain why these objects were able to fly through the air longer than the rectangular objects. Accept all answers. Return to your classroom. Show Video Clip 1 [00:42 to 01:46] on the Frisbee s angle of attack. After viewing the video, draw a diagram of an airfoil (see illustration) on the board. Ask students to comment on its shape. Explain that an airfoil is an object like an airplane wing. Its design helps lift it or control its flight through air. Airfoils are curved so that the air flows smoothly over their surfaces. This reduces the air resistance or drag. The lines on the diagram, called streamlines, represent the smooth paths of the flow of air over the airfoil. All lift-producing objects (e.g., kites, airplane wings, helicopter blades) work the same way they move through the air in such a way that the airflow produces a lift force. Tell students that airfoils are used in many types of items that need to fly (e.g., airplane wings, boomerangs, hang gliders, etc.) and that there are even some naturally occurring airfoils. The maple seed is probably the most commonly known; the Zanonia seed, from the Zanonia vine of tropical Asia, is an another example. Have some samples of airfoils for the students to look at (e.g., toy airplanes, Styrofoam gliders, boomerangs, etc.).! If it is appropriate, you may wish to view the entire Newton s Apple segment on Frisbee physics after completing the activity. 28 Frisbee Physics

29 Activity 1 Explore (Approx. 25 min.) Divide the class into groups. Explain that they are going to design and build an airfoil or flying wing. Distribute Activity Sheet 1. Have students gather the materials and make a flying wing patterned after an airfoil. When the students have completed their designs, they should conduct some test flights of the designs. Groups should adjust or change their designs if they don t initially work. The Guide on the Side provides some hints on adjusting the airfoils. When all groups have completed their airfoils, bring them together and discuss their experiences and conclusions. Evaluate 1. Several factors contribute to the flight of a Frisbee. Using a Frisbee, demonstrate how it flies. Describe what is happening as the Frisbee flies through the air. Explain the various factors that contribute to a stable flight. Demonstrate how the Frisbee flies when each factor is eliminated. Try This Experiment with airfoil modifications and explore the answers to these questions: How much nose weight is needed to ensure a long flight? What happens if the trailing edge of the wing is not curved upward? On average, how far do the wings glide? Try these variations and then demonstrate them to your class. Many different plants have aerodynamic seeds. Why is this? Collect flying seeds from your area. Research and make a bulletin board or set up a table to display airfoils in nature. What is the history of the Frisbee? What were the first Frisbees made of? How many companies make Frisbee-type discs? Research the history of Frisbees and report back to the class. 2. The shape of the Frisbee is an important feature that contributes to the flight of the Frisbee. Explain how shape influences flight. (Answers will vary, but should include the idea that the smooth, curved surfaces help the air flow smoothly, reducing the air resistance, or drag, while creating a lower air pressure on the top surface and contributing to lift..) 3. When you built your airfoil, you might have added a paper-clip weight to the nose of the glider and turned up the trailing edges of the wings. What roles did these design features play and how did the glider fly without them? (The weight gave the glider stability. Without it, the glider could not fly. The curved edges contributed to stability and controlled the direction of the flight.) Educational materials developed under a grant from the National Science Foundation 29

30 Flying Wing Activity Sheet 1 Name Class Period What you re going to do You and your group are going to design, build, and test fly an airfoil. How to do it Work with your group. Study the design of some common airfoils, like airplane wings and Frisbees, and come up with your own original flying wing. Here s one way of designing a flying wing: 1. Enlarge this airfoil wing template on this page. Trace the wing s outline, balance point and other markings on the bottom of a thin foam tray. Cut the shape out and use sandpaper to smooth the edges. 2. Use sandpaper to shape the surface of the wing to resemble an airfoil. 3. Tape a paper-clip weight securely in place. 4. Carefully bend up the tips of the wings. 5. Add additional weight to the nose if necessary until the glider hangs level or slightly nose down when balanced at the balance point. 6. Test your design and adjust it to make it fly better. Experiment with different ways of launching the wing. Recording your data In your journal, make sketches of your group s airfoil. Make notes about how it flew. Draw or describe adjustments you made to the airfoil. Record your observations of problems and how the group solved them. What Did You ou Find Out? What problems did you encounter? Which was the biggest problem and how did you solve it? Which launching technique worked best? Why? Compare your results and experiences with other groups. Discuss how other groups solved their problems. 30 Frisbee Physics Copyright Twin Cities Public Television & GPN. Permission granted to reproduce for classroom use.

31 Activity 2 Fantastic Frisbee Flying How fast and how far can a Frisbee fly? What happens when you throw a Frisbee straight up? How do you aim a Frisbee? Does the distance a Frisbee flies depend only on how hard you throw it? What would it be like to compete in a world championship Frisbee competition? Getting Ready Overview Students learn about the different types of long-distance throws, how to hold a Frisbee for a level flight, and how to release a Frisbee for the greatest spin. After they have had a chance to develop their skills, students gather data on how various throws affect the distance, time aloft, and accuracy of a Frisbee s flight. Objectives After completing this activity, students will be able to! determine the best methods for throwing a Frisbee to achieve different results! measure distances flown and times of flights for Frisbees thrown! compare and graph the distance thrown and the time of a flight when using different throwing techniques. Important Terms angle of attack The angle between the plane of an airfoil and the horizontal plane. lift The upward force exerted by air on an airfoil. drag Air resistance or the force of the air opposing the motion of the airfoil. Time Needed Preparation: Approx. 15 min. Classroom: Approx. 60 min. Materials For the teacher:! different types and sizes of Frisbees or other similar flying discs For each team of students:! Frisbees! stopwatch! measuring tape! calculator! pencils or pens Educational materials developed under a grant from the National Science Foundation 31

32 Frisbee Physics Here s How Video Clip 2 01:47 to 03:03 Jay Shelton shows David Heil that Frisbees need spin as well as lift to maintain a long flight. (1 min. 16 sec.) Video Clip 3 03:03 to 04:17 David Heil and Jay Shelton use angular momentum and torque to change a Frisbee s flight path. (1 min. 14 sec.) Guide on the Side! You may wish to begin the lesson by viewing the Introduction from the Video Menu on the CD-ROM [00:00 to 00:30]. Find out what students already know about Frisbee physics by discussing the questions posed by David Heil.! SAFETY NOTE: Locate a safe place for throwing Frisbees, either outside or in a large room such as a gymnasium.! If it is appropriate, you may wish to view the entire Newton s Apple segment on Frisbee physics after completing the activity. Preparation! Set up the computer to play the CD-ROM (or set up the VCR and cue tape).! Gather the materials for each team of students.! Make a copy of Activity Sheet 2 for each student.! Review the Background information on page 24.! Arrange for a Frisbee-throwing expert to demonstrate the various throws (the expert will probably be one of your students). Engage (Approx. 20 min.) Ask students what keeps a Frisbee stable as it flies through the air. (Accept all answers.) Then play Video Clip 2. Discuss the video and how the spin helps maintain the Frisbee s stability. Ask how you can use spin to control the Frisbee s flight path. (Accept all answers.) Play Video Clip 3. Discuss the throwing techniques shown in the video. Explain that the more spin given to a Frisbee, the faster, more accurate, and more stable its flight will be. Invite your Frisbee expert to demonstrate different methods of throwing a Frisbee and how to change the flight path. After the demonstration, tell students that they are going to explore different ways of throwing a Frisbee. Remind them that when they throw their Frisbees, they need to consider grip, body position, movement and release. Explain to students that there are many other types of throws that they may wish to try. (Some of these throws are listed at the end of the Explore section.) Explore (Approx. 40 min.) Organize the class into teams. Set up a Frisbee-throwing clinic so that students can help each other learn a variety of Frisbee-throwing techniques. Some of the throws can get quite complicated, so you might want focus on the principle techniques that contribute to Frisbee flight: grip, body position, movement and release (spin). After everyone has had the chance to practice, conduct a Frisbee-throwing Olympiad. As a class, decide which stations will be set up for testing different Frisbee-throwing techniques and how those techniques affect the flight of a Frisbee. Some ideas for stations are: accuracy in hitting a target; time aloft; distance; trick shots around trees or playground equipment; skip shots; etc. 32 Frisbee Physics

33 Activity 2 Distribute copies of Activity Sheet 3 to each team. Have the teams move from station to station, working together to figure out which throwing techniques are most applicable for each station. Use a record sheet for documenting performances at each station. Have students take three throws at each station. Record all three and calculate the average (if relevant to the station). Compare results with other teams. What types of throws produced the best results for each station? Did one type of throw work best for everyone at each station? Why or why not? Frisbee Throws air-bounce throw the Frisbee is thrown sharply toward the ground in a backhand throw, compressing the air beneath it and causing the Frisbee to rise backhand throw the traditional throwing style, in which the Frisbee is thrown across the front of the body; the back side of the hand moves through the air before releasing the Frisbee forehand throw the Frisbee is held with the index and middle finger underneath and the thumb on top and is released on the same side of the body as the hand holding it (also called the flick ) Try This Create a chart for the various types of throws using data from the entire class. Which types of throws resulted in the greatest distance? In the greatest time aloft? In the best accuracy? Display the chart on a bulletin board. There are many different Frisbee competitions and organized sports played with Frisbees freestyle, Ultimate, Frisbee golf, and Goaltimate. Research the rules for one of these Frisbee sports and organize an event for your class. Make your own Frisbee-like flying object. Design, size and materials will vary. Test your homemade Frisbee with some of the stations you used in this activity. How well did your homemade disc work? head throw the Frisbee is held as in the forehand throw but is released upside down from above the head skip throw the Frisbee is thrown so that the angle of release is opposite that of the normal throw; after the Frisbee strikes the ground, its direction of flight changes Evaluate 1. Demonstrate and describe several styles of Frisbee throws. Explain how each throw works and the effects each style will have on the flights of the Frisbee (e.g., how long it stays in the air, how far it travels or the route it takes). Demonstrate your favorite style of throw and explain what you like about it. 2. An expert can throw a Frisbee in such a way that it will travel several hundred feet. What factors must he or she control to get the maximum distance from a throw? (Answers may include a number of factors such as the force of the throw, the amount of spin, air resistance and angle of attack) 3. Spin is one factor that influences the flight of a Frisbee. Explain how spin is produced and how it contributes to the flight. Describe how a Frisbee might fly if spin were eliminated. (Spin is produced by the person throwing the Frisbee. Without spin, the Frisbee is not able to maintain a stable flight It will lose its angle of attack and quickly drop to the ground.) Educational materials developed under a grant from the National Science Foundation 33

34 Frisbee-throwing Olympiad Activity Sheet 2 Name Class Period What you re going to do Now that you ve practiced your throwing style, set up different stations to test the best Frisbee-throwing techniques for achieving different results, like distance, time aloft or trying to hit a target. Design a chart to record the results of your tests. (Use the one below as a guide; use the back of this paper for more tests.) Station (What is being measured?) Results Throw #1: Throw #2: Throw #3: Notes: Throw #1: Throw #2: Throw #3: Notes: Throw #1: Throw #2: Throw #3: Notes: 34 Frisbee Physics Copyright Twin Cities Public Television & GPN. Permission granted to reproduce for classroom use.

35 Activity 3 Friction-Friction-Friction What causes a spinning Frisbee to slow down and finally stop? Why do some people put lubricants on the undersides of their Frisbees? How can wearing fake fingernails improve your freestyle Frisbee stunts? Getting Ready Overview Students discuss what causes friction and how in some situations friction is desirable; in others, it is not. Through a simple activity, students compare the frictional effect of different surfaces on a block sliding down a ramp. Objectives After completing this activity, students will be able to! describe examples of friction between objects that move past one another! explain methods used by competitors to reduce friction of spinning Frisbees! determine which of several different surfaces has the least amount of frictional effect on a sliding block. Important Terms friction The force that appears to resist or slow down the motion of an object. fluid friction The force that results when an object moves through air or liquids. sliding friction The force that results when the surface of an object slides over the surface of another object. rolling friction The force that results when an object rolls over the surface of another object irregular Not uniform, straight, nor symmetrical Time Needed Preparation: Approx. 20 min. Classroom: Approx. 50 min. Materials For each team of students:! smooth-surfaced board for constructing a small ramp (a piece of laminated wood from a bookshelf works well)! books! wooden blocks several pieces of materials with different textures (e.g., carpet! linoleum, sandpaper, velvet, satin, aluminum foil, etc.)! tape! tape measure Educational materials developed under a grant from the National Science Foundation 35

36 Frisbee Physics Video Clip 4 05:02 to 06:36 David finds out that a well-oiled Frisbee has less friction then watches some Frisbee experts at work. (1 min. 33 sec.) Guide on the Side! You may wish to begin the lesson by viewing the Introduction from the Video Menu on the CD-ROM [00:00 to 00:30]. Find out what students already know about Frisbee physics by discussing the questions posed by David Heil.! If blocks won t slide down the ramp, suggest that students make the ramp steeper by adding books.! Some students may have difficulty measuring and recording their results. It might be helpful to demonstrate the proper way to measure the distance traveled. Make sure students start the blocks at the exact same point each time.! You might wish to review how to calculate an average, or mean, of three or four numbers.! As always, it is a good idea for you to work through the activity before using it with your students.! If it is appropriate, you may wish to view the entire Newton s Apple segment on Frisbee physics after completing the activity. Preparation Here s How! Set up the computer to play the CD-ROM (or set up the VCR and cue tape).! Gather the materials for each team of students.! Make a copy of Activity Sheet 3 for each student.! Review the Background information on page 24. Engage (Approx. 10 min.) Have students rub their hands together quickly. Do they feel heat? Ask students if they know what causes the heat. (friction) Did they notice that as they rub their hands together, the frictional forces are greatest in the areas that have the most contact? Discuss ways in which the friction between their hands could be reduced. Ask students to give you different examples of friction. List examples on the board. Explain that these examples represent different types of friction. List four types of friction on the board fluid friction, sliding friction, and rolling friction. Have students try to match the examples with a type of friction. Explain that sliding friction was what they experienced when they rubbed their hands together. Sliding friction occurs whenever the surface of one object slides over the surface of another object. The amount of the sliding frictional forces between two surfaces depends on the materials they are made of and how firmly they are pressed together. Friction also occurs in fluids liquids and gases. Fluid friction occurs when an object moving through a fluid pushes aside some of the fluid. Ask students if they ve ever run through water. Was it easy or difficult? Running through water can be difficult even at low speeds because of the amount of friction fluid friction. Air resistance is another form of fluid friction. It is also the friction that acts on something that is moving through the air. Rolling friction is what makes the tires on a car or truck heat up after it has been driven a few miles. Ask what friction might have to do with a Frisbee. Accept all answers. Play Video Clip 4 [05:02 to 06:36]. Discuss how the competitors reduced the friction of the spinning Frisbee. Could similar methods be used to reduce the friction created by rubbing your hands together? How long would the Frisbee spin if there were no friction? (Theoretically it would spin forever.) 36 Frisbee Physics

37 Activity 3 Explore (Approx. 30 min.) Divide the class into teams and distribute Activity Sheet 3. Have each team of students construct a ramp and test the friction that is created between different surfaces. Their tests should include several measures using a variety of materials. The data collected during the activity should be carefully recorded so that it can be analyzed and graphed. After all teams have completed collecting data, analyze and graph each team s findings as a class. Evaluate 1. Friction can have undesired effects. For example, friction (drag) has a negative effect on the flight of a Frisbee by slowing it down and causing it to drop from the air. However, friction is also important to many things we do. Describe several examples of how friction makes our lives safer and easier. Try This Why is reducing friction in a car important? Talk to an auto mechanic and ask about the different kinds of lubricants used in a car. Find out how each lubricant reduces a certain kind of friction. Report your findings to the class. A Frisbee encounters air friction as flies. Is there a way of reducing this friction with a lubricant? Set up an experiment and see if a lubricant, such as an oil or silicon spray, will allow the Frisbee to fly farther. Report your findings to the class. 2. The video mentioned that Frisbee competitors oftentimes don t have much left of their fingernails. Explain why this is the case. What techniques do Frisbee competitors use to overcome the limitation of not having natural fingernails? (The competitors natural fingernails are worn down by the friction created by the spinning Frisbees. Artificial plastic fingernails create less friction than softer,, natural fingernails, and are more durable. This reduction in friction allows the spin of the Frisbee to continue for a longer period of time. In addition, lubricants are used to reduce friction.) 3. Imagine you are looking through a microscope at a close-up view of the surface of an apparently smooth piece of metal. Draw a picture of what you might see. Label your drawing and explain how this surface would produce friction if it came in contact with another surface. How can the friction be reduced? (The drawing should show that even apparently smooth surfaces have irregularities. These irregularities create friction. Lubricants help fill in the rough spots to reduce friction.) Educational materials developed under a grant from the National Science Foundation 37

38 Activity Sheet 3 Friction, Friction, Friction Name Class Period What you re going to do You re going to investigate how different surfaces create different amounts of friction. How to do it Using available materials, construct a ramp with a slope that is steep enough so that your block easily slides all the way down to the bottom of the ramp. Then construct a test to compare how the block slides (or doesn t!) when the ramp is covered with a different material. Make sure the materials are applied evenly, with no wrinkles. Discuss with your team how you think the surface will affect the slide of the block. Carefully position the block at the top of the ramp. Then, let go. (Do not push it!) Measure the distance the block slid, and record it. Slide the block at least three times on each surface, then find the average distance traveled. Change the surface material and repeat the activity. Recording your data ta In your journal make a data table to record your data. Your table might look like the one below. Surface material Stopping distance Trial 1 Trial 2 Trial3 Average distance What Did You Find Out? Which material produced the least friction against the block? How do you know? What materials not available for this test today might have produced even less friction? In the video, lubricants were used to reduce friction. What effect would the use of lubricants have on your findings in the activity? Compare your results with those of other groups. What might account for any differences? 38 Frisbee Physics

39 Credits PROJECT DIRECTORS Dr. Richard C. Hudson Director of Science Unit, KTCA-TV, St. Paul, MN David R. Heil Associate Director, Oregon Museum of Science and Industry, Portland, OR Gregory C. Sales, Ph.D. Associate Professor, Curriculum and Instruction, University of Minnesota, Minneapolis, MN KTCA-TV PROJECT TEAM Lee Carey Project Manager Paddy Faustino Project Coordinator David Yanko Production Manager NEWTON S APPLE MULTIMEDIA Michael Watkins Senior Project Manager David Heath Curriculum Development Manager Kay LaFleur Cori Paulet Curriculum Development Coordinators Mike Paddock Production Manager Jeffrey Nielsen Producer/Scientist Profile Coordinator Ben Lang Additional Resources Coordinator Janet Raugust CD Graphics Designer J. Michael Gatlin Jay Miller Lawrence Sahulka Video Graphics Designers J. Michael Gatlin Illustrator NEBRASKA EDUCATIONAL TELECOMMUNICATIONS John Ansorge Interactive Media Project Manager Andy Frederick Interactive Media Designer Christian Noel Interactive Media Project Designer Kate Ansorge Intern GREAT PLAINS NATIONAL Tom Henderson Jackie Thoelke Nikki Naeve Guide Design and Production NATIONAL ADVISORY BOARD M. George Allen 3M Research and Development Rodger Bybee Biological Sciences Curriculum Study Richard C. Clark Minnesota Department of Education, Retired Helenmarie Hofman Gettysburg College Dave Iverson Imation Enterprises Corporation Dr. Roger T. Johnson University of Minnesota Dr. Mary Male San Jose State University Dr. Carolyn Nelson San Jose State University Lori Orum Edison Language Academy Yolanda M. Rodriguez Martin Luther King, Jr. School Talbert B. Spence American Museum of Natural History Janet Walker B.E.T.A. School Michael Webb New Visions for Public Schools SENIOR ADVISORS David Beacom National Geographic Society Dr. Judy Diamond University Of Nebraska State Museum Dr. Fred Finley University Of Minnesota Greg Sales Seward Learning Systems, Inc. LESSON EDITORS Bonnie B. Graves Richard Graber Elizabeth Frick Betty Flannigan LESSON WRITERS Jules Beck Michael Damyanovich Karen DeYoung Elizabeth Frick Katherine Hooper Tim Kochery Christopher Lee Sue Mattson Michael Mazyck Luther Rotto Ali Simsek John Shepard RESOURCE SPCIALIST Steve Bryan SCIENCE ACTIVITY SPECIALIST Steve Tomecek INSTRUCTIONAL DESIGN ASSISTANT Annette Mittlemark OFFICE ASSISTANT Rebecca Johnson SCIENCE CONTENT REVIEWERS Fred N. Finley, Ph.D. University of Minnesota Steve Fifield, M.A. University of Minnesota George Freier, Ph.D. University of Minnesota Clayton F. Giese, Ph.D. University of Minnesota Patricia Heller, Ph.D. University of Minnesota Mark Hollabaugh, Ph.D. Normandale Community College (MN) Murray S. Jensen, Ph.D. University of Minnesota Ron Keith, Ph.D. Emporia State University (KS) FORMATIVE AND SUMMATIVE EVALUATIONS Karen Hoelscher, Multimedia Research Assistant Poressor, Educational Curriculum and Instruction Western Washington University, Bellingham, WA Ralph Adler, RMC Research Corporation Portsmouth, NH FIELD TESTERS/EVALUATORS Mr. Michael Ahren Portola Valley School District Portola Valley, CA Mr. Robert Aniba Weyauwega-Fremont Middle School Weyauwega, WI Ms. Barb Bannister Portland, OR Mr. James Bell Trendyffrin/Easttown Middle School Berwyn, PA Ms. Beryl Bell Bradenton Middle School Bradenton, FL Ms. Claudia Berryman-Shafer Fernley, NV Ms. Teresa Bettac Willis Intermediate School Delaware, OH Mrs. Noyce Bischoff Santa Catalina Lower & Middle School Monterey, CA Ms. Darleen Brabec Malone School Prescott, WI Mr. Stephen Burke Woonsocket Junior High School Woonsocket, RI Mr. David Bydlowski Stevenson Junior High School Livonia, MI Ms. Skip Caddoo Lesher Jr. High School Ft. Collins, CO Ms. Sarah Carlson Heppner Middle School Heppner, OR Ms. Maryanna Claxton Science Resource Teacher Brainerd, MN Educational materials developed under a grant from the National Science Foundation 39

40 Credits Mr. Anthony Cody Bret Harte Jr. High Oakland, CA Mr. David Kendall Cook Oceanside High School Oceanside, CA Ms. Kristine Craddock Mexico Public Schools Mexico, MO Ms. Maureen Cunningham P.S. 219 Flushing, NY Ms. Mary Jane Davis Red Bank Catholic High School Red Bank, NJ Ms. Karen Doerrter Harper s Choice Middle School Columbia, MD Ms. Evie Donald Hopkins West Junior High School Minnetonka, MN Ms. Barbara Foster Robinson Middle School Robinson, KS Ms. Susan Fourneia Cleveland Quality Middle School St. Paul, MN Mrs. Jane Lusk Starkville High School Starkville, MS Ms. Jeanne Luttschyn Maltby Middle School Brighton, MI Ms. Jayne Meyer Elmonica Elementary Schoo; Beaverton, OR Mr. Greg Morrison Goddard Middle School Glendora, CA Mr. Kenneth Murphy Medford Public Schools Medford, MA Mr. Robert Nelson Walkersville Middle School Walkersville, MD Mr. Kevin Noack Watson Jr. High Muleshoe, TX Ms. Laura Norsworthy Mandeville Middle School Mandeville, LA Mr. Peter O Neil Waunakee Middle School Waunakee, WI Mr. Jim Schrankler Como Elementary School St. Paul, MN Ms. Meredith Schweighart Wynne Jr. High School Wynne, AR Ms. Sally Shaffer Indiana Area Junior High School Indiana, PA Ms. Maria Shield James Bowie High School Austin, TX Mrs. Jean Siesener Ladue Junior High School St. Louis, MO Ms. Mitzi Smith Thurmont Middle School Thurmont, MD Mr. James Stearns Bristol High School Bristol, SD Mr. Jim Stern Westwood Middle School Blaine, MN Mr. Larry Strand Simle Junior High School Bismarck, ND Mr. David Galliher Carmichael Junior High School Richland, WA Ms. Kathleen Glenn Washington Jr. High School Chicago Heights, IL Ms. Becky Goodwin Kansas State School for the Deaf Olathe, KS Mr. Mark Gugisberg Champlin Park High School Champlin, MN Ms. Dorothy Hattan Hammond Middle Schol Laurel, MD Mr. J. Steve Joyce North Quincy High School Quincy, MA Mr. Paul Jutrzonka Morse Middle School Milwaukee, WI Ms. Kathy Kay Kincaid Salem, OR Ms. Harriet Kmet Indian Trail Junior High Addison, IL Mr. John Larabee Thomas Ewing Junior High School Lancaster, OH Ms. Franceline Leary Troy High School Troy, NY Ms. Mary Loomer Hoover Intermediate School Waterloo, IA 40 Credits Mr. John Olson Murray Magnet Junior High School St. Paul, MN Mr. Todd Pierson Pillsbury Math Science Technology Magnet Minneapolis, MN Mr. Gary Pinkall Great Bend Middle School Great Bend, KS Ms. Cathie Plaehn Tiffany Creek Elementary Boyceville, WI Ms. Kathy Rackley Buist Academy for Advanced Studies Charleston, SC Mr. C.R. Rogers Rancho San Justo Middle School Hollister, CA Ms. Barb Romano Deforest Area Middle School DeForest, WI Ms. Ninfa Ruiz-Diaz Johnston High School Austin, TX Ms. Ruth Ruud Walnut Creek Middle School Fairview, PA Ms. Robin, Rybarczyk Sacred Heart School Saratoga, CA Mr. Steve Sample Sandburg Junior High School Elmhurst, IL Ms. Julie Scheuermann Vineyard Junior High Alta Loma, CA Ms. Marjorie Stueckemann Twin Groves Jr. High School Buffalo Grove, IL Mr. Bob Talbitzer Kearney High School Kearney, NE Mr. James Valente Dreyfus Intermediate School 49, R Staten Island, NY Ms. Laura Walsh Thompson Junior High School Bakersfield, CA Mr. Donna West Bay Trial Middle School Penfield, NY Mr. Lanny Whitten Kennebunk High School Kennebunk, ME SPECIAL THANKS Larry Bachman Thomas Carr Jim Caspar Kris Dokmo Evelyn Donald Trich Flock-Johnson Aletha Halcomb Dick Hinrichs Emily Hoover Ken Meyer Paul Musegades Paul Neff Arnold Nelson Jack Netland Todd Pierson Sheldon Ramnaine Brad Randall Lawrence Rudnick Hank Ryan Vince Smith Dianne Strandberg Dave Tucker Judy Tucker Mark Zuzek

41 NOTES

42 NOTES

43 AT LAST, a supplemental middle school science curriculum that helps you meet the challenges of today s science classroom. The program engages students by incorporating segments from the award-winning Newton s Apple television show into hands-on/minds-on activities. Each lesson plan helps you integrate the technology using an inquiry-based approach. A variety of assessment options allow you to gauge student performance. And the entire program is correlated to the National Science Education Standards. EACH CURRICULUM MODULE CONTAINS: a CD-ROM with two Newton s Apple segments, a video profile of a working scientist, and additional audio/visual resources a teacher s guide with lesson plans for six inquiry-based activities a Newton s Apple videotape 38 topics in 19 modules!! Choose the curriculum modules that benefit your needs. Physical Science Life Science and Health Earth and Space Science Air Pressure/Domed Stadiums Antibiotics/Cancer Clouds/Weathering Electric Guitars/Electricity Blood Typing/Bones Dinosaur Extinction/Earthquakes Gravity/Rockets DNA/DNA Fingerprinting Everglades/Sewers Infrared/Reflection Hearing/Human Eye Geothermal Energy/Glaciers Newton s Laws/Doppler Effect Nicotine/Smiles Greenhouse Effect/Ozone Frisbee/Buoyancy Meteors/Solar Eclipses Skydiving/Roller Coasters Phases of the Moon/The Sun Sports Physics Hang Gliding/Surfing High Wire/Skateboards Spinning/Water-skiing Individual Packages: $49.95 To order by mail: To order by phone, call toll-free: Three-CD collection: $ Four-CD collection: $ Fax your order to: your order to: P.O. Box gpn@unl.edu Lincoln, NE Order today!

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