Engineering Adventures

Transcription

1 Engineering Adventures Engineering Journal Name:

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3 Adventure 1 Message from the Duo reply forward archive X delete from: to: subject: engineeringadventures@mos.org You Can You Hear That? 3:09 PM Sain baina uu (pronounced san-ban-oh)! That s hello in Mongolian! We are in Mongolia, a country in Asia between Russia and China. We sent you a map so you can see where we are. We re here for a festival called Naadam (pronounced nuh-dahm.) It happens in July. During Naadam, there is music and dancing, archery, wrestling, and horse riding competitions. We were invited by our friend, Zaya (pronounced ZI-ya.) He is helping out at the festival. Zaya is an acoustical engineer. Have you heard the word acoustics before? Acoustics has to do with sound and acoustical engineers design technologies that control sound. Concert halls, speakers, and musical instruments are just some of the technologies acoustical engineers design. Have you ever been near a highway and heard how loud the noise from cars and trucks can be? Acoustical engineers also design barriers that block noise from highways so it is not so loud for people living nearby. Zaya said there may be some sound-related problems we can help him solve at the Naadam festival. He told us that in order to help him engineer, we must first learn about how sound works. What is sound? Can we see it? How does sound reach our ears and how does it move through different materials? Imagine We sent some materials so you can experiment with sound. Keep track of what Ask you find, because it may be helpful later! The Goal Plan India and Jacob Improve Create 1

4 Adventure 1 World Map This is Mongolia! 2

5 Adventure 1 Sound Introduction All sound starts as a vibration. What happened when the jug was hit? Vibrations move through the air. When the jug is hit, it creates sound vibrations. When the vibrations hit your ear drum, you hear the sound! When the jug was hit, sound vibrations made the salt move. Even though we cannot see the sound vibrations, they have energy that can make things move! 3

6 Adventure 1 Exploring Sound For this challenge, you will need: 1 metal spoon 1 pair of scissors 30 inches of string 30 inches of yarn 30 inches of fishing line Step 1: Lay the piece of string straight out on a table. Place the spoon in the middle of the string. Tie the string to the handle of the spoon, so there are two pieces of string the same length on either side of the spoon. Step 2: Wrap the ends of the string around each pointer fingers. Put your pointer fingers in your ears to block your ears. Step 3: Swing the spoon so it hits a solid table or chair and listen to the sound that is produced. Step 4: Repeat using the yarn and fishing line. How would you describe the sound you hear using the string? How would you describe the sound you hear using the yarn? How would you describe the sound you hear using the fishing line? 4

7 Adventure 2 Message from the Duo reply forward archive X delete from: to: subject: engineeringadventures@mos.org You Can You Hear Me? 9:18 AM Hi Engineers, India and I had a lot of fun learning about how sound travels through air and other materials! Here in Mongolia, Zaya showed us the speaker they are going to use at the Naadam festival. Unfortunately, the sound that comes out is really quiet and we can t turn it up any louder. He said we will need to figure out how to increase the volume. Zaya suggested the first thing we test is how different materials affect the volume of sound. He told us that sometimes when sound hits a material, it can bounce off the material and continue to travel. This is what happens when you hear an echo, and it is called reflection. Zaya also said that sometimes sound hits a material and is absorbed. The material acts like a sponge, in this case, so the sound doesn t bounce back as much and the volume decreases. We sent you pictures to help you visualize what happens when sound is reflected and when it is absorbed. We need you engineers to test different materials to see which ones reflect and which ones absorb sound. Can you help us? We can t wait to hear about your results! Imagine Jacob Ask The Goal Plan Improve Create 5

8 Adventure 2 Hearing Sound Sound can be reflected or absorbed by different materials. Reflection: Sound can bounce off of materials. Materials that reflect sound allow the sound to bounce off of them so we hear them at the same volume. Volume remains the same. Absorption: Sound can be absorbed by some materials. When sound hits these materials, they act like sponges and absorb some sound, so the volume of the sound we hear is reduced. Volume is reduced. 6

9 Adventure 2 Telephone Directions To make one telephone you need: 1 piece of string, 5 feet long 2 cups with a small hole in the bottom 2 washers For materials testing: 2 sheets of construction paper 2 sheets of foam 2 sheets of foil, 1 foot 2 sheets of transparency Step 1 Pull one end of your string through the hole in the bottom of one cup. Step 2 Tie a washer to the end of the string. Step 3 Pull until the washer is against the bottom of the cup. Step 4 Repeat with the other end of the string and the second cup. Step 5 Place the cutouts inside each cup, using one material at a time. How does the volume of the sound change when you use different materials? 7

10 Adventure 2 Materials Testing To Use: Hold the cup tight to your mouth. Whisper a message to your partner or instruction for them to follow. For example: raise your left foot or wave with your right hand. Turn so your ear is facing your partner. Hold the cup tight to your ear, blocking your other ear with your hand. Can you hear your partner? Follow your partner s instruction if they give you one. Keep the connecting material tight! Good: Bad: Rate the Volume: Test the telephone lined with each material. In the chart below, rate how well you can hear the message your partner gives you by circling the number that best describes what you can hear: Material 0 I cannot hear anything. Rating 1 I can hear sound but cannot hear what is being said. 2 I can hear the message from my partner. No material Construction Paper Foam Foil Transparency

11 Adventure 3 Message from the Duo reply forward archive X delete from: to: subject: engineeringadventures@mos.org You Shaping Sound 10:41 AM Hi everyone, Were you as surprised as we were to hear how sound bounces off different materials? We have been trying to think of other ways to create louder sounds. Zaya told us that acoustical engineers use the word amplify to describe an increase in volume. This means we have been figuring out what materials help amplify sound! We brought along kazoos for our trip to Mongolia. Have you heard of this instrument? If you hum into it, it vibrates to create a louder sound! Zaya pointed out that engineers can use shapes to make sounds louder. The shape can bounce the sound in a certain direction and make it louder. Do you think you can design a shape to add to the kazoo that amplifies the sound? Zaya also showed us a cool tool called a decimeter. It measures the volume of sounds. We sent you one so that you can accurately measure the volume of the sounds you make! Use the Engineering Design Process to help you imagine, create, and test different shapes to add to the kazoo. We can t wait to hear which shapes are good at amplifying the sound of the kazoo. Ask The Goal Imagine Plan India Improve Create 9

12 Adventure 3 Shapes What do you notice about the shape of these different instruments? Creative Commons Bardentrefen_2010_1020 by Ralf Schulze is licensed under CC BY 2.0 Creative Commons 2015 Sonoma July 4th Parade by Sarah Stierch is licensed under CC BY 2.0 Creative Commons Blow Gabriel Blow by Canon in 2D is licensed under CC BY 2.0 Creative Commons scot by Martin Abegglen is licensed under CC BY 2.0 Creative Commons Aguiluchos Marching Band by Prayitno is licensed under CC BY

13 Adventure 3 Kazoos 1. HUM HERE (DON T BLOW) 2. THE SOUND COMES OUT HERE 3. THE EXTRA AIR COMES OUT HERE TIP: If you do not get a sound, say the word who in the kazoo. Testing Procedure TEST 1: Pick one group member to test the kazoo. Hold the kazoo over the X, and make sure your educator is ready with the decimeter. Hum into the kazoo. Record the number on the decimeter on the next page TEST 2: Hold the shape your group made snugly around the circular cap on the kazoo. Have the same group member hum the same way as in the first test. Record the number on the decimeter on the next page Write your name in permanent marker on your kazoo. 11

14 Adventure 3 Acoustic Shape Ideas Record the volume of the kazoo with and without your shape. Shape 1 Without Shape With Shape What is the difference? Shape 2 Shape 3 Which shape amplified the volume the most? Draw it below. 12

15 Adventure 4 Message from the Duo reply forward archive X delete from: to: subject: engineeringadventures@mos.org You The Festival is Almost Here! 8:55 AM Hi Engineers, Congratulations! You have done a great job asking questions about how shape and materials affect the way sound is amplified. Now it s time to use what you have learned. We are currently in the Mongolian capital of Ulaanbaatar (pronounced u-lan-ba-tar), and the Naadam festival is coming up fast. The festival always starts out with a big opening ceremony in a wide open field. Remember how the volume of our speaker is already low? Since the ceremony is in a field and not a stadium, the sound from our speaker cannot bounce off of any walls. This makes the volume of our speaker even harder to hear! Zaya has asked us if we can help him engineer an acoustic device that can amplify the music that is played over the speaker during the opening ceremony of the festival. We sent you a speaker with some traditional Mongolian music to test with. Have you ever been to a festival before? At a festival there are many people in a lot of different locations, and they all need to hear the music. Can you design an acoustic device that can amplify the music at two different locations Imagine in the field where the opening ceremony will take place? Ask The Naadam festival is fast approaching, and we really need your help! Jacob Improve The Goal Create Plan 13

16 Adventure 4 Acoustic Device Draw Your Plan Use the space below to draw a plan of your acoustic device. What materials will you use? Label your picture below. TEST RESULTS: Record the volume at each location using your acoustic device. What improvements would you like to make to your acoustic device? Location #1: Location #2: 14

17 Adventure 5 Message from the Duo reply forward archive X delete from: to: subject: engineeringadventures@mos.org You Make it Even Better 10:41 AM Hi everyone, Jacob, Zaya, and I really like your acoustic device designs so far! Zaya told us acoustical engineers improve and test their designs as often as they can to make sure their technologies work as well as possible. They test to see how loud the sound is from different areas of the field where the audience will be standing. We heard thousands of people are coming to the Naadam festival! The field will be filled with people during the music performance. We know that we need to amplify the music to people who will stand in front of the speaker. What about the audience who will be behind the speaker? Do you think you can improve your device so that it amplifies the sound behind the speaker as well? The Naadam festival is right around the corner! Can you improve your acoustic devices so that we re ready to jam?! India Imagine Ask The Goal Plan Improve Create 15

18 Adventure 5 Improve What will your improved acoustic device look like? What materials do you need? Draw a picture or write below. TEST RESULTS: Record the volume at each location using your acoustic device. Location #1: Location #2: Location #3: 16

19 Adventure 6 My Next Engineering Adventure For the Record I would like to be an acoustical engineer. Yes No Maybe so Why or why not? What do you want to engineer next? Draw your technology here! My engineering checklist: Find friends to work with. Ask questions about how to start. Imagine lots of ideas. Make a plan. Create and test the plan. Improve until you think it is ready. What materials will you use? 17

20 Sound Glossary Absorption: The process by which a material takes in some or all of the sound energy when a sound bounces off it. Absorption causes the volume of the sound to decrease. Acoustic device: A technology related to sound. Acoustical engineer: An engineer who designs technologies that solve problems related to sound. Amplify: The process of increasing the volume of sound. Decibel: Unit of measurement that describes the volume of sound. Decimeter: A tool used to measure the volume of sound. Reflection: The process by which sound waves bounce off a material. Sound: Vibrations transmitted through matter. Volume: The loudness of a sound. 18