By

Katherine Crunk

Unit Overview

This unit contains five science lessons about sound written in the Five E

Learning Cycle format. The first lesson introduces students to sound as energy that

is transferred to surrounding objects in sound waves. In the second lesson, students

explore the qualities of sound pitch and volume by using first different sized rubber

bands and then straw flutes that the students create. In the third lesson, students

determine how sound travels through different states of matter and the absence of

matter. In the fourth lesson, students examine reflection and absorption of sound

by observing how sound responds with different materials. In the fifth lesson,

students explore how different hearing adaptations help animals survive including

echolocation. Furthermore, each lesson incorporates technology. Several lessons use

on-line simulators to assist in exploring sound waves. Additionally, on-line video

clips help extend and explain concepts of sound.

Lesson 1: Sound – Transfer of Energy

Grade level: 5 - 6

Concept: Sound is created by interaction of objects that create vibration. Sound energyis transferred to surrounding objects in sound waves that can cause vibration andmovement in objects that interact with the sound waves.

Objectives: The students will be able to identify sound as a form of energy. The studentswill be able to describe how sound energy transfers.

Standard/Benchmark: Strand IV: Using Scientific Knowledge in Physical Science,Standard (PWV) IV.4: All students will describe sound and sound waves: Middle 6:Explain how mechanical energy transfers energy: Key concepts: Sound energy,absorption, transmission, reflection; media (Michigan curriculum framework, 2000)

Materials:

For engage: Two ballsThin strip of paper approximately ½ inch wide by 5 inches long (1 forteacher and 1 for each group)TapeSound Tapper (1 for each group) constructed from

Cardboard tube (such as toilet paper roll or paper towel roll)Heavy paper cut out into same size as end of cardboard tube.Single small hole in center of heavy paper made by sharp pencilHeavy paper circle taped to one end of cardboard tube.Plastic wrap cut large enough to stretch over other end of tubeRubber band around plastic if necessary to hold plastic(Neil Ardley, 2006, p. 76)

For Explore: Supply the following for each groupPlastic bowlsPlastic wrap (enough to stretch over top of bowl)Large rubber band (used if necessary to secure plastic)Salt (couple of pinches)Rice Krispies (handful)Various objects to make sound: Should include: Milk jugs, metal lids tojars, teaspoons, plastic mixing spoons, wood block

For Explain: Have at least one computer with internet connection. Preferably, have onecomputer or laptop for each group.

Safety Concerns (if any): Students should keep “Sound Tapper” and all other objectsused to create sound away from ears as preventative measure. Students should keep faceaway from plastic covered bowl to prevent salt from entering eyes. Salt and RiceKrispies should be disposed up properly in trash. Do not eat.

Prior Knowledge: In previous Learning Cycle, students learned about mechanicalinteractions and transfer of energy.

Engage:1) Begin the lesson by accessing students’ prior knowledge about energy transfers. Showthe students two balls and roll one at the other sitting still hitting it.2) Ask the students, “How did the still ball move?”Possible student answers: the rolling ball hit the other ball and made it move, the movingball transferred energy to the still ball making it move.3) After this little demonstration, show the students the “Sound Tapper” and demonstratehow to use it. Do this by taping the strip of thin paper to a table or desk that is visible tothe students. 4) Pass out one “Sound Tapper” to each group, a strip of paper, and piece oftape allowing each group to experience the “Sound Tapper.”5) Question the students as to what they think might be happening to make the papermove. “Is the paper moving because of air movement or because of sound? Can soundcause things to move?” Today we will investigate sound to answer this question, “Cansound move objects?6) To explore this question, what kind of things might we try?” Try hitting differentthings.7) Show students the setup of plastic pulled tightly over a bowl. Place about 1/4 teaspoonof salt on plastic and a handful of Rice Krispies (Ardley, 2006 p. 75).8) Ask: If sound can move objects, what factors might be involved?” Have studentsbrainstorm and write their ideas on the board. The ideas for factors might include size ofmaterial on plastic, how you tap, how close you tap, how hard you tap, how soft you tap,where you are above, or at side and what you use.9) Give each group the variety of items to test.

Explore: Students will explore the question “Can sound move objects.” Instruct thestudents on safety issues. Instruct the students to keep records of what items were used,how the items were used, and what observations were made. Remind the students thatwhile they try different sounds they need to make sure that they are not causing airmovement that could interfere with their observations. Allow approximately seven to tenminutes for exploration.

Explain: To begin the Explain, ask the students for the results of their explorations. Ifstudents performed many tests, have them share up to three that they found to be the mostinteresting to them. Record the results on large table on overhead or board.

1: From the data that was collected, what can we say about sounds ability to make thingsmove. Can sound cause things to move?

The students should respond that sound can move objects.2: What else can be said about sound and movement?

According to the collected observations, the closer the sound is to the objects thegreater the movement, the louder the sound greater the movement and differenttypes of sound create more movement than others.

3: Think back to mechanical interactions. How did we know that an interaction betweenobjects occurred?

Some kind of change happens in the objects that are interacting. These changesinclude change in speed, direction, temperature, and shape. The objects that areinteracting are involved in a system of interactions.

4: What evidence do we have of interactions in our sound experiment? We heard asound and saw vibration in the salt and Rice Krispies. In order for interactions to takeplace, energy is needed and that energy is transferred from an energy source (orgiver) to an energy receiver.

In our experiment, when one object struck another, energy was transferred fromone object to the other. The evidence of energy transfer is the vibration in one ormore of the objects involved and the sound that we heard. The vibrating objects thentransfer sound energy to air molecules touching the vibrating objects causing the airmolecules to move bouncing off each other like a chain reaction. Scientists call thismovement of molecules that transfer sound energy, sound waves. When the movingair molecules run into other objects, such as the plastic on the bowl, energy wastransferred causing the plastic to vibrate, which in turn, transferred energy to the saltand Rice Krispies causing them to vibrate and jump.

5: Bring up the “Sound Interference” simulator on the web sitehttp://phet.colorado.edu/web-pages/simulations-base.html. Show the students theparticle display of the sound wave to help explain the motion of the molecules in theair involved in a sound wave. Discuss the action of the particles and explain that isshows an example of how the molecules in the air move to transfer energy.

Items Used Actions Observations/ measurementsMilk jug and plastic mixing spoon Hit hard & close Rice Krispies and salt vibratedMilk jug and plastic mixing spoon Hit hard & far Salt vibratedMilk jug and plastic mixing spoon Hit soft and close Rice Krispies and salt vibratedMetal lid and metal spoon Hit at side and close Nothing happenedMetal lid and metal spoon Hit over top and close Salt vibrated and few Rice KrispiesPop bottle and plastic mix. Spoon Hit bottom of bottle with

open end facing bowlRice Krispies and salt vibrated

Extend and Apply:1: We have now established that the sound that we hear is evidence of an interaction that

involves sound energy being transferred. We also saw how the sound energy transfersthrough the air in sound waves. Since we hear the sound, are we involved in some waywith the sound system? How are we involved?

2: Inform the students that the class is taking a quick sound hunt. Instruct the students tolisten for and to select a sound. Take a quick walk down the hall or outside.

3: Upon returning to the class, have the students write a paragraph describing the soundthat they found. Include in their description an explanation of how the sound is made.They can do this by identifying what objects are interacting, what energy is beingtransferred, and from what to what? Include everything that you can think of that isinvolved in the sound system. Include with the paragraph a drawn picture or diagramto help explain the paragraph.

Performance Assessment: Collect paragraphs and pictures to assess understanding ofsound as a form of energy and how sound energy transfers.

Source(s):Ardley, N. (2006). Sound and music. In P. Bailey, N. Hazle, H. Parker, J. Vaughan, & A.

Weir (Eds.), 101 great science experiments. New York: DK Publishing.Berger, C. F., Berkheimer, G. D., Lewis, L. E., & Neuberger, H. T. (1979). Exploring

energy: Sound energy. In Science. Atlanta: Houghton Mifflin.Michigan curriculum framework (2000) (Electronic Version) Retrieved on February 14,

2007 from Michigan Department of Education web site:http://www.michigan.gov/documents/MichiganCurriculumFramework_8172_7.pdfl

Sound interference. (2006). PhET: Physics Education Technology. Retrieved February 1,2007, from University of Colorado Web site: http://phet.colorado.edu/web-pages/index.html

Lesson 2 of Sound

Sound – Qualities of Sound - Pitch and Volume

Grade level: 5 – 6

Concept: Pitch is how we perceive sound and is created by sound waves with high orlow frequency (or the rate of vibration.) Volume is result of high or low amplitude (or theamount of energy transferred to create the sound.)

Objectives: Students will be able to identify properties of sound, such as pitch andvolume. The students will be able to explain how these properties relate to the motion ofvibrating objects in terms of frequency and amplitude.

Standard/Benchmark: Strand IV: Using Scientific Knowledge in Physical Science,Standard Waves and Vibrations (PWV) IV.4 All students will describe sounds and soundwaves: Elementary 1. Describe sounds in terms of their properties. Key concepts:Properties: pitch—high, low. Loudness—loud, soft. Real-world contexts: Sound fromcommon sources, such as musical instruments, radio, television, animal sounds, thunder,human voices. All students will measure and describe vibrations and waves: MiddleSchool 5. Describe the motion of vibrating objects. Key concepts: Period, frequency,amplitude. Real-world contexts: Vibrating or oscillating objects, such as weights onsprings, vocal cords, tuning forks, guitar strings (Michigan curriculum framework, 2000)

Materials:

Engage: Either an instrument (recorder, flute, guitar, or any other instrument) or a CD ofan instrument (preferably a single instrument)

Explore: 1 for each group: Rubbermaid or reusable Glad container preferably 8 cuprectangular shape

1 set for each group: 4 Rubber bands of varying sizes and of different colors (The bandsshould be large enough to stretch over container once but varied enough in size so thatsome fit tightly and some fit loosely. The bands should be consistent between each groupto aide in communication about results.)

Extend: 5 straws for each student

Clay (small ball equal to about one tablespoon for each student)

Scissors and tape

Safety Concerns: Students should take care with stretching rubber bands and weargoggles to prevent eye injury. Containers should be held away from face while stretching.During the extend portion of the lesson students should not walk around while blowinginto the straws and should remain seated to avoid injury with straws.

Engage: Begin the lesson with a reminder of what was discovered in the previouslesson: Ask the students for a volunteer to remind the class what we learned in theprevious lesson. The desired response should include that we found that sound is madeby vibrations in one or more objects interacting and energy being transferred in the formof sound energy through sound waves.Next, play for the students an instrument or CD of an instrument. If playing aninstrument, play different notes at different volumes. If using a CD select music thatdemonstrates varying volume, playing softly and playing loudly. After playing theinstrument or CD, ask the students “how the sounds differed. Was each sound the same?”Student responses might include loud, soft, low, high and the sounds were made by thesame thing. Teacher: “From what we heard, sounds produced from the same object canhave different qualities. The sounds can be loud or soft, high or low. Question: “Whatcauses the changes in sound?” Tell the students that today we are exploring sound usingplastic containers and rubber bands. Show the students how to place 1 rubber band

around the plastic container and pluck to make sound. Teacher: “Our job today is toexplore and discover what factors are involved in changing sound.” Make a list togetherof different factors that the students predict might have an influence on changing thesound by first listing possible factors for volume (softness and loudness) and by secondlylisting possible factors for pitch (highness and lowness).

Explore: The students will explore the question, “What causes changes in sound?” Passout the materials to each group. Instruct the students on safety concerns. Have thestudents record data for each band by recording in order of size smallest to largest, resultof highness and lowness comparing each band and observations of vibrations. Also, havestudents explore how to change volume on a single band and record results. Allow tenminutes to explore. Share collected observations by making a classroom chart onoverhead or board by listing order of bands by size, order of the sounds heard, andvibration observations. Additionally, list observations regarding changing volume on asingle band.

Explain: To begin the Explain, ask the students for the results of their explorations.

1: From the data that were collected, what can we say about what causes changes insound. What factors are involved in changing sound?

The students should respond that the smallest bands fit the tightest, vibrated thefastest, and produce the highest sound. In addition, the largest bands fit theloosest, vibrate the slowest, and produce the lowest sound.

From the data, what can we say about what causes change in the loudness of a sound?

The students should respond that the harder you pluck the louder the sound andthe softer you pluck the quieter the sound.

2: Let’s first look at highness and lowness of sound. In our rubber band instruments, wefound that the tighter rubber bands produce a higher sound and that the looser rubberbands produced the lowest sound. Scientists have a name for the highness or lownessof sound. Scientists call this pitch. We also observed that the rubber bands of differenttightness also vibrated differently. The larger looser bands vibrated more slowly,which produced a lower pitch and the smaller tighter bands vibrated more quickly,which produced a higher pitch. From the first sound lesson, we learned that soundenergy is transferred in sound waves by vibrating molecules in objects interactingwith surrounding molecules of air and other objects. How quickly or how slowly an

Order of Bands by Size and Fiton Plastic Container

Comparison of Highnessand Lowness (Pitch) Observations of Vibrations

Purple – smallest – fits tightest Highest sound Fastest, moves the least distance in vibratingRed HighYellow LowBlack – largest – Fits loosest Lowest sound Slowest, moves the farthest in vibrating

Change in volume: found that you pluck soft for soft sound – pluck hard for loud sound.

object vibrates determines how we hear the sound, the pitch of the sound. Scientistsuse the word frequency to describe the vibration and sound waves. Frequency is thenumber of times an object vibrates per second. The pitch describes how “our braininterprets” the vibration and sound waves (Baptiste, H. P., Daniel, L., Hackett, J.,Moyer, R., Stryker, R., & Vasquez, J., 2002. p. F55). Therefore, to study the pitchwe can look at the frequency of a sound. Scientist use a device called an oscilloscopeto observe sound waves. The oscilloscope draws a type of graph of the sound givinga simple picture.

3. In the “Sound Interference” simulator, we can play with the pitch, hear the pitch, andsee a graph of the sound. Bring up the “Sound Interference” simulator on the website http://phet.colorado.edu/web-pages/simulations-base.html. Show the students thegraph of the sound waves. Turn on the volume. Change the frequency. Let thestudents observe the change in pitch compared to the change in frequency. Show thepicture display in particle and sound waves to help the students understand the motionof the vibration compared to the frequency.

4. In our experiment, we also explored what caused the change in loudness or whatcaused the change in volume. We observed that the harder we plucked the louder thesound and the softer we plucked the softer the sound. When we pluck harder, we areputting more “what” into the interaction? Energy. The amount of energy that is putinto the vibration determines the volume of the sound. Scientists call the amount ofenergy, amplitude.

5. In the same “Sound Interference” simulator with the graph displayed, show how lowamplitude, or not much energy looks on the graph compared to more energy and highamplitude. Demonstrate with the simulator more energy given to the vibration showsas higher peaks and lower valleys on the graph resulting in more volume anddemonstrate the opposite.

Extend and Apply: (Adapted from Baptiste, H. P., Daniel, L., Hackett, J., Moyer, R.,Stryker, R., & Vasquez, J. (2002) “Explore Activity: How can you change a sound?”)

1. Our rubber band experiment resembled a string instrument. Question: “Do allinstruments use strings?” Students answer should be “no.” Ask for examples of differenttypes of instruments. Some instruments use a column of air that vibrates to create soundinstead of a string that vibrates, such instruments include flutes, piccolos, and pipeorgans.

2. Pass out five straws and small clump of clay to each student. Tell the students that theirtask is to create an instrument that uses vibrating columns of air made from straws.Demonstrate how to use clay to stop one end of the straw and how to blow across theopen end to create a sound.

3. What can you do to create different pitches? Write a prediction of what needs to bedone to have different pitches. Have the students first write their predictions down on apiece of paper.

4. Test your prediction. Once you are satisfied with the results use tape to join the strawsin order of lowest to highest pitch. Demonstrate how to tape the straws together.

5. On the paper with your prediction, record your results by laying your instrument flaton your paper tracing around it and labeling the pitches from highest to lowest. On thepaper, also include an explanation of how your instrument works to create sound and tocreate different pitches (think about the vibration observations in our rubber bandexperiment.) Finally, on your paper answer the question, “if you wanted to play theinstrument loudly what would you have to do?”

(Write this on the board)

Your paper needs:

1) Your prediction

(2) A tracing of your instrument

(3) Label on your tracing with the order of pitches from highest to lowest pitch.

(4) Explain how your instrument works to create sound (what is vibrating) and how yourinstrument plays different pitches.

(5) Explain what you would have to do to increase the volume of the sound. What wouldyou have to increase?

Performance Assessment: Collect the papers with the students’ predictions, tracing ofstraw instrument, and explanation to determine students understanding of pitch,frequency, volume, and amplitude.

Source(s):

Baptiste, H. P., Daniel, L., Hackett, J., Moyer, R., Stryker, R., & Vasquez, J. (2002).Sound Energy. In Science. New York: McGraw Hill.

Baptiste, H. P., Daniel, L., Hackett, J., Moyer, R., Stryker, R., & Vasquez, J. (2002).Explore Activity: How can you change a sound?. In Science. New York: McGrawHill. P. F55.

Michigan curriculum framework (2000) (Electronic Version) Retrieved on February 14,2007 from Michigan Department of Education web site:http://www.michigan.gov/documents/MichiganCurriculumFramework_8172_7.pdfl

Sound interference. (2006). PhET: Physics Education Technology. Retrieved February 1,2007, from University of Colorado Web site: http://phet.colorado.edu/web-pages/index.html

Lesson 3: Sound – Transfer Through Matter

Grade level: 5 – 6

Concept: Sound travels through different media such as solids, liquids, and gases. Soundcannot travel through a vacuum.

Objectives: Students will be able to describe how sound travels through different statesof matter. Students will be able to describe how sound does not travel through a vacuum.

Standard/Benchmark: Strand IV: Using Scientific Knowledge in Physical Science,Waves and Vibrations (PWV) IV.4 All students will describe sound and sound waves:Middle 6: 1. Explain how sound travels through different media. Key concepts:Media—solids, liquids, gases. Vacuum. (Michigan curriculum framework, 2000)

Materials:Explore: provide for each group the following:

Non-digital timer (must have ticking sound)Two metal spoonsYardstickMetal yardstick or similar objectDishpan (or similar container) filled with water.Data recording handout

Extend:Either one computer per group, per child (lab cart) or teacher station computerInternet connection

Safety Concerns: Use goggles as different items will be held up to your face. Allequipment should be used as directed. Only one person should dip ear into water as this isa health issue. Water should be disposed of carefully in the sink. Any spilt water shouldbe wiped up immediately.

Engage: In our first lesson we learned that sound is created from vibrations that travelsin waves.Teacher: As we hear sounds all around us, what do sound waves travel through?

Students: AirTeacher: What is air? Is it a solid, liquid, or gas?

Students: GasTeacher: Since air is a gas and we can hear sounds, what can we say about soundtraveling though a gas? Can sound travel through gas?

Students: We can say that sound can travel through gas.Teacher: Has anyone ever been swimming in a pool or a lake and heard sounds under thewater. What did you hear?

Students: Yes (listen to responses)Teacher: What is water? Is it a solid, liquid, or gas? Students: Liquid

Teacher: If water is a liquid, what can we say about sound waves transferring through aliquid?

Students: We can say that sound can travel through a liquid.Teacher: If sound can travel through a gas (air) and a liquid (water), do you think soundwould be able to travel though a solid? What could we do to test this?

Take suggestions. Try possible suggestions, which should include putting ear totable or desk and tap on the table.

Teacher: From what we just tried, what can we say about sound traveling through asolid? Can sound travel through a solid?

Students: We can say that sound can travel through a solid.Teacher: If sound travels through solids, liquids, and gases, which state of matter cansound travel through the best: gas, liquid, or solid. Today we will be testing soundsthrough different matter to see what sound travel though the best. Each group will begiven different materials and different items to make sound. Use one sound maker at atime to test each item. Make a chart of each item and record how each sound was heardthrough the item. Keep record of which item allowed you to hear the sound the best andthe worst.When you get the materials, you are trying to identify what state of matter does soundtravel through best: gas, liquid, or gas.

Demonstrate with a volunteer, how one student will hold the item to one ear whilecovering the other ear if necessary. Another group member will hold the sound makeragainst the item testing or gently tap with the object to create sound. For gas and solid,each item will be tested in the same manner with the same sound before switching. Ineach group of four, pair up to hold sound and to listen. One holds the sound while theother listens. Go through all items for that sound. Record observations about how well thesound traveled through the item and then switch, the listener holds the sound now and thesound holder listens now. For the liquid, one member of the group will volunteer to putear into the water to listen. Only one student will listen in the water. The other studentwill tap spoons together under the water.

As you perform your tests, what question are we trying to answer? Studentsshould respond, “What state of matter does sound travel through best?”

Explore:

1. Pass out the recording sheet and have students make predictions before testing objects.2. Instruct the students on safety issues.3. Pass out the materials.4. After each material and sound is tested, each group is to talk over the data collectedand write a statement summarizing their observations as to what transfers sound the best,solids, liquids, or gases.

Explain:

On the overhead projector, consolidate the students’ data.

Matter Sound 1: timer Sound 2: toybeeper

OverallObservation

Gas - air Can barely hear Can hear okLiquid waterSolid wood Can hear loud Can hear loud &

clear

Solid transferredthe best. Air wasthe least best.

Solid metal Can hear loud Can hear loud

From our data, what can we say about sound waves and different states of matter?Why might this be? First, let us think about sound. How does sound travel? Soundtravels in waves as energy is transferred from one molecule to another.How are the molecules in different states of matter arranged?

In gas?In liquid?In solid?

How does this relate to what we found in our testing?The state of matter with the closest molecules transfers sound the best. Therefore,

solids transferred sound the best. This is because the molecules are closer have to travelless distance to transfer the sound waves. Gases have the loosest arrangement ofmolecules and therefore are the slowest in transferring sound. This is because themolecules are farther apart and have to travel greater distance for sound waves totransfer.

Extend and Apply: In our exploration and previous experience, we found that soundtravels through all sorts of matter. However, we did not investigate if sound can travelthrough a vacuum like outer space. We know light can travel through space. That is howwe have sunlight on earth from the sun. However, can sound travel through space wherethere is no air or matter?1) Have each student on a sheet of paper write a prediction to this question and give theirreasons/ evidence for their prediction based on the information learn about sound andstates of matter.2) If enough computers are available, have the students either go onto the computers ingroups or individually. If enough computers are not available, use teacher’s station.3) Go to http://phet.colorado.edu/web-pages/simulations-base.html. Click on simulatorsfor sound. Click on “Sound” simulator, click on “Listen with varying air pressure”, andclick on green box to remove air from box. Use this simulator to test your prediction.4) On the paper with your prediction, write what you observed and how it compares toyour prediction and reasons for prediction.5) Include a picture with explanation of how sound travels through each state of matter.Show how the molecules are arranged in each state of the matter. In your drawing,compare these to a vacuum by including a picture of what happens to vibrating objects ina vacuum. Explain your drawing.

Performance Assessment: To assess the students, first observe the students during theExplain and Extend to make sure the students understand the concepts. For finalperformance assessment, collect the vacuum predictions and explanations paper with

drawings of the states of matter to assess students’ understanding of how sound travelsthrough matter and the absence of matter.

Source(s):Michigan curriculum framework (2000) (Electronic Version) Retrieved on February 14,

2007 from Michigan Department of Education web site:http://www.michigan.gov/documents/MichiganCurriculumFramework_8172_7.pdfl

Sound. (2006). PhET: Physics Education Technology. Retrieved February 1, 2007, fromUniversity of Colorado Web site: http://phet.colorado.edu/web-pages/index.html

Lesson 4 Sound – Reflection and Absorption

Grade level: 5 - 6

Concept: As sound waves travel, it interacts with different objects that can vary thesound as some of the sound is transmitted, reflected, or absorbed by the objects.

Objectives: The students will be able to explain reflection and absorption of soundwaves as it applies to the transfer of sound energy.

Standard/Benchmark: Strand IV: Using Scientific Knowledge in Physical Science,Standard (PWV) IV.4: All students will describe sound and sound waves: Middle 6:Explain how mechanical energy transfers energy: Key concepts: Sound energy,absorption, transmission, reflection; media (Michigan curriculum framework, 2000)

Materials:

For each group provide:Two long cardboard tubes (wrapping paper tube) or newspaper rolled to form tubes.A ticking watch or timerVarious materials: wooden block, brick, towel, cookie sheet, ceiling tile, sponge,craft foam sheets

For the Extend/Apply:Teacher station computer

Safety Concerns (if any): Care should be taken when handling the brick. Studentsshould be careful not to drop the brick as it could cause damage to school property orperson.

Engage:

To begin the lesson, talk with the students about painting a room in your house. Ask thestudents if any of them have had a room painted, maybe their bedroom. Ask the studentsto describe how the room was different once all of the furniture was removed. If thestudents do not mention how the room sounded different, lead them with the question,“When the room was empty, did it sound different than when the room was full offurniture?” If it sounded different, do you think that the things in the room affected theway sound traveled in the room? Today we are exploring to find the answer to thisquestion. “How do different materials affect the way a sound travels?” In the last lesson,we explored how sound travels through different states of matter. We found that soundtravels the best through solids. Today we want to explore how different materials affectthe way sound travels. Each group will be given two tubes, a ticking watch or a timer,and different items. Show the class how to setup the materials to explore the question.Place the two tubes at an angle to each other with one of each ends close together asdemonstrated in this diagram. The other ends at the edge of the table to make it easier toput ear up to the tube. Demonstrate how to listen in one tube with the sound at the othertube. Have a student help hold the timer.

(Pass out the Prediction/Observation tables one to each student). Before you start toexplore the question,” How do different materials affect the way a sound travels,” Make aprediction of which of the items will be the loudest and which will be the quietest. Use ascale of 1 to 5 with 5 being the loudest and 1 being the quietest. Make sure eachindividual in your group listens with each material. Test each material, makeobservations, and prepare to answer the question, “How do different materials affect theway a sound travels?”

Explore: (Adapted from: (2002). Sound Energy. In Science. Published in New York byMcGraw, authored by Hill.Baptiste, H. P., Daniel, L., Hackett, J., Moyer, R.,Stryker, R., & Vasquez, J. page F65 – F 67)

(Watch orTimer)

Differentmaterials

Before the students start, instruct them about safety concerns. Pass out the materials forthe Explore. Allow the students at least fifteen minutes to explore the question, “How dodifferent materials affect the way a sound travels?” Make sure the students understand thequestion they are exploring.

Explain: To begin the Explain, ask the students for the results of their explorations.Record the results on large table on overhead or board as follows.

1: From the data that were collected, what can we say about how different materialsaffect sound? Does sound behave in the same way for all materials?

Different materials affect the sound in different ways.2: For what materials did sound behave similarly? How did the ticking sound with thosematerials?

The wood and cookie sheet was the loudest.The towel and ceiling tile was the quietest.The craft foam and sponge was in the middle.

3: What do the cookie sheet and the wood block have in common?They both have smooth surfaces.

What does the towel and ceiling tile have in common?Both items are not smooth. The towel is soft but not smooth. The ceilingtile is hard but not smooth.

4: From our observations, we found that sound does not respond the same with allmaterials. Different materials affect sound differently. When sound struck a hard, smoothsurface, like the cookie sheet, the observed sound was louder than the sound that struck asoft, textured surface, like the towel. Remember in previous lesson, we learned that soundis energy that is transferred from molecule to molecule from a vibrating object to alistener’s ear. When sound energy strikes a hard, smooth surface, some of that energywill travel through the object as we observed in the last lesson, and much of the energywill bounce off the surface. When the sound bounced in our exploration, we could hearthe sound in the tube. This is called reflection. When sound comes in contact with atextured surface, it responds differently. Some of the energy will pass through the

Material Observation

Group 1 Group 2 Group 3 Group 4 Group 5

Wood block 4 5Brick -- --Towel 1 1Cookie sheet 5 4Ceiling tile 1 1Sponge 2 2Craft foam 3 3

textured object as we learned in the last lesson. Some of the energy might reflect off thesurface. However, with items like the ceiling tile and the towel, most of the energy willenter the object and stop, changing into heat energy. When the sound stops and changesinto heat energy, this is called absorption.

Extend and Apply:Therefore, in our empty bedroom what is happening?

Sound is reflecting off the bare walls. The reflected sound that we hear is calledan echo. When the echo is real good, you can hear your words repeat back. Sometimes,the echoed sound sounds fuller, as though there is more than one sound maker. When theroom is full, different soft materials absorb some of the sound preventing an echo.Where might the ideas of sound reflection and absorption be important to use? Whatplaces would find it important?

Places such as orchestra halls, operas, movie theaters, live stage theaters, meetingrooms, churches.

Areas where musical instruments are played can affect how the instrument sounds.On the teacher’s station for the whole class to watch go tohttp://www.exploratorium.edu/music/exhibits/headlands/index.html. Click on videonumber seven “Inside Out.”Tell the students:Watch this short one-minute movie. Something strange will happen. Be on watching andsee if you can identify what is strange. Something is just not right. Do not tell anyone.(Play the movie twice.)On a piece of paper, answer the questions. (Write these on theboard.)

1. Did you see or hear something strange, something just not right?2. What was it?3. Using what we learned today about sound energy, absorption, reflection, and

echoes, explain why this strange happening is just not right.

First collect the paper and then have the students discuss what was strange and why.

Performance Assessment:Assess the students for understanding first by observing them during discussion in theExplain and Extend to make sure that they understand the concepts of reflection andabsorption. For final performance assessment, collect the papers about the movie. In thispaper, look to see if the students understood reflection and absorption of sound wavesand was able to relate it to transferring of sound energy.

Source(s):

Baptiste, H. P., Daniel, L., Hackett, J., Moyer, R., Stryker, R., & Vasquez, J. (2002).Sound Energy. In Science. New York: McGraw Hill. P F65 –F67

Michigan curriculum framework (2000) (Electronic Version) Retrieved on February 14,2007 from Michigan Department of Education web site:http://www.michigan.gov/documents/MichiganCurriculumFramework_8172_7.pdf

Science of music: Headlands experiments. (2006). Retrieved April 15, 2007, fromExploratorium: The museum of science, art, and human perception Web site:http://www.exploratorium.edu/music/exhibits/headlands/index.html.

Lesson 5: Sound – Adaptations & Echolocation

Grade level: 5 - 6

Concept: The position and shape of the ears on an animal affects the reception ofsound. Some animals have ears that are able to move to help locate a sound. Someanimals emit sounds that bounce off objects to locate objects such as food. Theseabilities are adaptations that allow animals to use sound to help them survive.

Objectives: Students will be able to identify the position, shape, and mobility of ears asan adaptations of animal to help them survive. Students will be able to describe the usesound to locate objects by echolocation.

Standard/Benchmark:Strand III: Evolution (LE) III.4: All students will compare ways that living organismsare adapted and reproduce in their environments and explain how species (suited) tosurvivechange through time: 2. Explain how physical and behavioral characteristics of animalshelp them to survive in their environments.Key concepts: Characteristics—adaptation, instinct, learning, habits. Traits and theiradaptive values—Sharp teeth or claws for catching and killing prey, color forcamouflage, behaviors.

Strand IV: Using Scientific Knowledge in Physical Science, Standard (PWV) IV.4: Allstudents will describe sound and sound waves: Middle 6: Explain how mechanical energytransfers energy: Key concepts: Sound energy, absorption, transmission, reflection; media(Michigan curriculum framework, 2000)

Materials:Overheads or pictures on projector of mammalsOverhead of prediction and observation chartPVC tube listening devices – one set of two per group. Use 18 inch long with two-inch

diameter pipe. On one end, attach a PVC elbow. If possible, use a double twistingelbow for better positioning.

A different sound maker for each group such as a bell, clicker, paper to crumple, pencilstapping, and a beeping toy.

White board for each group.Computer teacher’s station with internet connection

Safety Concerns Students should not run or walk around while holding PVC tubes toears.

Engage:We have been studying sound, how sound energy travels through matter, and how soundcan be reflected and absorbed. We now know that sound is an energy that is transferredfrom a vibrating source that travels in sound waves. We hear sound when the soundwaves interact with our ears. Show the students pictures of mammals’ ears. What do younotice about these mammals’ ears?

They all have ears. They all have two ears. The shapes of the ears are different.Some ears are close together. Some are far apart.

All ears are used for hearing. We all know that we hear with our ears, but does thelocation of the ears make a difference in hearing? Ask the students “how can we test thequestion, ‘Does positioning of the ears help animals locate a sound?’” The teachershould write the student’ suggestions on the board.

Show the students the PVC tube listening devices. Demonstrate how to hold thetubes to your ears to change the position of the sound being directed into the ears. Howcould you use these to test ear position?

Responses might include: put on ears and point up, down, out to the side,forward, backward, and to opposite sides.

Have the students in each group select at least four different positions to test.(Show the Prediction/Observation overhead)

(1) Using the overhead as a guide, write the positions down on a piece of paper that youwill use to answer the question, “Does the position of the ears help animals locate asound”(2) Next make a prediction of the ability to hear the sound from each position. Comparedto your normal ears would the sound be just as easy to locate, the same, easier to locate,or harder to locate.

Each group will receive a different sound to help you listen for your group’s sound. Taketurns in making the sound, in listening, and in recording how your listener did. Oneperson will stand to test one of your selected positions. The listener should close theireyes and keep them closed. The sound maker will quietly move to a different spot aroundthe listener and make the sound. When the listener hears the sound, should turn towardsthe sound facing the direction from where the sound came. Try the sound from differentareas. The observer should write down how the listener did. Write down if the listenerseemed to have difficulty or if he/she found the sound right away.

Have a student help demonstrate this procedure.

Position Prediction Observation

Pointing

Pointing

Pointing

Pointing

Pointing to oppositesides

Explore: Before the students start, instruct them about safety concerns. Pass out thePVC tubes for the Explore. Instruct the students to summarize their findings in words or achart on a white board to share with the class. Allow the students at least 10 to 20minutes to explore the question “Does the position of the ears help animals locate asound?” Make sure the students understand the question they are exploring.

Explain: To begin the Explain, ask the students for the results of their explorations.Display the students white boards. Have each group share their findings and conclusion.

Position Prediction ObservationPointing forward Best with sound in front.

Hard from behindLocated fast when in front, harderfrom the sides, hardest frombehind

Pointing up Hard to find sounds Hard to locate sounds, easier thanjust pointing front though

Pointing back Best with sound in backHard from the front

Located sound fast in back, harderat side, hardest in the front

Pointing to oppositesides (left to right andright to left)

Same as normal Hardest to find the sound,confusing

1: What are some similarities in each group’s observations?The sounds were the easiest to hear when the tubes were pointing towards the sounds.When the tubes were pointing to the opposite sides, it was hard to locate the sound.

2: From these observations, what can we say about how the number of ears and thepositions of the animals’ ears help to locate sounds? From our observations we can saythat animals can also hear best when their ears are pointing in the direction of the sound.

3: Why would this benefit animals? Predators could find food easier and prey could hearthe predator and hide. Some animals have developed ears that help them survive to locatesounds. Go tohttp://www.teachersdomain.org/resources/tdc02/sci/life/reg/animalhear/index.htmlplay video entitled “Animal Hearing” (1 min. 48 sec.)For example: Dogs have more than 18 muscles to tilt, rotate, and raise their ears. This allows

dogs to rotate their ears almost 180 degrees. The shape of dogs’ ears allowssounds to be directed into the inner ear.

Cats have about 30 muscles in the ear allowing for excellent directional hearing.Cats can move each ear independently to pinpoint sounds.

Compare this to humans. We have only 6 muscles that control our ears and mostof us cannot even wiggle our ears. However, the shape of our outer ear allowssound from different directions to be captured and directed into the middle ear.

The position of the barn owl’s ear holes allows it to hear so exactly that it canhear prey in the dark and attack without seeing it. The owl’s ear holes arepositioned under a tuft of feathers. This tuft forms a cone shape to capture sound.Additionally, the owl’s ear holes are positioned at different heights, one higherthan its eyes and one lower than its eyes. This allows the owl to determine theheight of a sound. If a sound is above the owl, the sound will be captured first bythe higher ear hole and if a sound is below, the sound will be captured by thelower ear hole first.

These are just a few examples of how animals have adapted hearing to aid in survival.

Extend and Apply:

Most animals depend on sight to locate objects and use hearing to locate sounds fromobjects. However, some animals have adapted to be able to use sound to locate objects,almost like sight. Animals with this ability make a sound, the sound travels in a soundwave that reflects off the surface of objects, and returns to the animal giving the animal atype of picture of the object. By hearing the reflected sound, the animal can find objectssuch as food even in the dark. This ability is called echolocation. Can anyone name ananimal that uses sound to locate objects?

Bats, dolphins, and some whales use sound to locate objects.Watch video clip about echolocation in dolphins.http://www.junglewalk.com/popup.asp?type=v&AnimalVideoID=171. Do you thinkhumans could use echolocation to locate objects? People do use a device called sonarthat sends a signal to the ocean floor. The sound reflects back to the sonar device givingan image of the floor of the ocean and objects under the water. Nevertheless, the questionis “Can humans use echolocation like dolphin? Why or why not?”On a piece of paper,1. Can humans use echolocation like dolphin? Why or why not? Are our ears designed(adapted) to be able to do this?2. Support your answer with what we have learned about sound and sound waves.3. Draw a picture of what using echolocation would look like for a human, demonstratinghow the sound waves would respond.

Write the questions on the board or overhead for the students to answer. After answering,watch the video of an amazing teenager.http://www.cbsnews.com/stories/2006/07/19/earlyshow/main1817689.shtml.

Performance Assessment: Collect the paragraph and pictures to assess students areable to identify the position, shape, and mobility of ears as an adaptations of animal tohelp them survive and able to describe the use of echolocation.

Source(s):

Baptiste, H. P., Daniel, L., Hackett, J., Moyer, R., Stryker, R., & Vasquez, J. (2002).Sound Energy. In Science. New York: McGraw Hill. P F65 –F67How do bats do that. Retrieved April 16, 2007 from Friends of the KartchnerCaverns State Park web site:http://www.explorethecaverns.com/lessons/guide2a.html

Michigan curriculum framework (2000) (Electronic Version) Retrieved on February 14,2007 from Michigan Department of Education web site:http://www.michigan.gov/documents/MichiganCurriculumFramework_8172_7.pdfl

How a blind teen sees with sound. (2006). Retrieved on April 17, 2007 from: The earlyshow: CBS:http://www.cbsnews.com/stories/2006/07/19/earlyshow/main1817689.shtml

Ultimate guide dolphins. (1999). Retrieved April 17, 2007 from Discoverycommunications website:http://www.junglewalk.com/popup.asp?type=v&AnimalVideoID=171

Teacher’s domain. (2007) Retrieved on April 17, 2007 from WGBH EducationalFoundation website:http://www.teachersdomain.org/resources/tdc02/sci/life/reg/animalhear/index.html

A dog’s ears and hearing. (2005) Retrieved April 17, 2007, from Pet health 101 website:http://pethealth101.com/ear/ear_hearing.shtml