Chapter Resources for Differentiated Instruction Waves

Transcription

1 Title Chapter Resources for Differentiated Instruction Waves Page Lesson 1 Lesson 2 Lesson 3 Level Get Ready to Read 1 all students Quick Vocabulary 3 all students Student Lab Safety Form 5 all students Launch Lab all students Content Vocabulary ELL all students Lesson Outline ELL all students MiniLab all students Content Practice A AL OL BL Content Practice B AL OL BL Language Arts Support 52 all students Math Skills 32 all students School to Home all students Key Concept Builders AL OL BL Enrichment all students Challenge AL OL BL Lesson Quiz A AL OL BL Lesson Quiz B AL OL BL Skill Practice 40 all students Lab A AL OL BL Lab B AL OL BL Lab C 69 AL OL BL Chapter Key Concepts Builder 70 AL OL BL Chapter Test A AL OL BL Chapter Test B AL OL BL Chapter Test C AL OL BL Answers (with Lesson Outlines) T2 T17 AL Approaching Level OL On Level BL Beyond Level ELL English-Language Learner Teacher evaluation will determine which activities to use or modify to meet any ELL student s proficiency level.

2 Copyright by The McGraw-Hill Companies, Inc. All rights reserved. Permission is granted to reproduce the material contained herein on the condition that such materials be reproduced only for classroom use; be provided to students, teachers, and families without charge; and be used solely in conjunction with the Glencoe Middle School Science program. Any other reproduction, for sale or other use, is expressly prohibited. Send all inquiries to: Glencoe/McGraw-Hill 8787 Orion Place Columbus, OH ISBN: MHID: Printed in the United States of America QWD

3 To The Teacher This book contains reproducible pages that support the Student Edition. Descriptions and frequencies of these resources are listed in the table that follows. Title Frequency Overview Get Ready to Read: What do you think? 1/Chapter Using the Get Ready to Read anticipation guide in the Student Edition? This page matches the anticipation guide in the Student Edition. Students can complete this at the beginning of a chapter and check their responses at the end. Appropriate For all students Quick Vocabulary 1/Chapter Need some options to preteach vocabulary and help students with vocabulary development? By folding the Quick Vocabulary sheet in half, students will have an easy reference tool. Lesson vocabulary, along with academic vocabulary, review vocabulary, or multiple-meaning words, are listed and defined. Students can add other words that they need to remember as well. all students Student Lab Safety Form 1/Chapter Need a standard lab safety form? Each FastFile includes this form that students can complete prior to each lab. Students indicate that they understand all aspects of the lab. There is a place for the student and you to sign it. all students Launch Lab Content Vocabulary* Lesson Outline* MiniLab 1/Lesson 1/Lesson 1/Lesson 1/Lesson Want a lab recording page for Student Edition Launch Labs? Each recording page matches the Student Edition Launch Labs, so students do not need to use their textbooks in the lab. Want to help students who need more vocabulary practice? Content Vocabulary pages provide review and reinforcement activities. Use these pages to help students master content terms. Want an outline of the chapter for a substitute teacher, for absent students, or for students to use for review? Lesson outlines follow the head and subhead structure of the Lesson, emphasizing the major content objectives. They can be used in many ways. In addition to those listed above, they can help you organize teaching notes and accompany student reading. Want a lab recording page for Student Edition MiniLabs? This recording page matches the Student Edition MiniLab, so students do not need to use their textbooks in the lab. all students all students all students all students AL Approaching Level OL On Level BL Beyond Level * ELL English-Language Learner Teacher evaluation will determine which activities to use or modify to meet any ELL student s proficiency level. Waves iii

4 Title Frequency Overview Appropriate For Content Practice (Leveled) 1/Lesson Need more options for content review? Content Practice A is designed to help students who have difficulties learning and understanding the vocabulary and Key Concepts of each lesson: Form A helps struggling students grasp lesson content AL AL AL Form B provides on-level and beyond-level reinforcement of lesson content AL OL BL Language Arts Support 1/Chapter Looking for a way to help students build reading and writing skills in science? Language Arts Support pages provide practice using vocabulary, language structure clues, and writing skills with science content. all students Math Skills 1/Chapter Want help for students who need to practice math skills? This page provides additional practice of the Math Skill in the Student Edition. all students School to Home 1/Lesson Looking for a way to help students with the content? The School to Home page provides support for a home-learning partner to help a student better understand the Big Idea of a chapter. all students Key Concept Builders Enrichment Challenge Lesson Quiz (Leveled) 4/Lesson 1/Lesson 1/Lesson 1/Lesson Have students who need more practice with Key Concepts? Key Concept Builders present the content in a context different from the Student Edition. These pages can be used whenever a student is struggling with any of the lesson s Key Concepts. Looking for ways to help students to broaden their understanding of lesson concepts? Use Enrichment pages to further explore information and Key Concepts introduced in a lesson. Want to motivate the independent learner? The Challenge activity extends information in the Student Edition and challenges a student s abilities. The activity can be completed in class or at home. Need options to evaluate students after each lesson? These quizzes are developed around the Key Concepts of a lesson: Quiz A provides more guided questions Quiz B provides more short-answer and completion questions AL AL AL all students AL AL BL AL AL OL BL AL Approaching Level OL On Level BL Beyond Level * ELL English-Language Learner Teacher evaluation will determine which activities to use or modify to meet any ELL student s proficiency level. iv Waves

5 Title Frequency Overview Skill Practice 1/Chapter Need a lab recording page for the Skill Practice? This corresponds to the Skill Practice in the Student Edition. Write-on lines are included for answers. Tables/ charts/graphs are included for recording observations, or space is provided for drawing tables/charts/graphs. Students do not need to use their textbooks in the lab. Appropriate For all students Want leveled lab recording pages for the Lab in the Student Edition? These pages provide leveled versions of the Student Edition Lab. Write-on lines are included for answers. Tables/charts/graphs are often included for recording observations, or space is provided for creating tables/charts/graphs: Lab (Leveled) 1/Chapter Version A This version follows the student edition lab but each step of the procedure is broken down sentence by sentence. Included are check-off boxes that provide easier processing for struggling learners. AL AL AL Version B This version is the student edition lab. AL OL BL Version C This version is designed to be a challenge for independent learners. Students must complete version B before doing version C. AL AL BL Chapter Key Concepts Builder Chapter Test (Leveled) Teacher Pages 1/Chapter 1/Chapter Have students who need more practice with Key Concepts related to the Big Idea? This practice page is designed to reinforce chapter content for struggling students before they take the chapter test. Need options to assess each student according to his or her abilities? These leveled chapter tests accommodate all students: Version A provides students with more guided questions Version B more short-answer and completion questions Version C challenges students with more difficult and open-ended questions Want all the answers in one place? These pages contain the answers for all the practice pages. AL AL AL AL AL AL AL OL AL AL AL BL AL Approaching Level OL On Level BL Beyond Level * ELL English-Language Learner Teacher evaluation will determine which activities to use or modify to meet any ELL student s proficiency level. Waves v

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7 Get Ready to Read Waves What do you think? Before you read, decide if you agree or disagree with each of these statements. On the line before each statement, place an A if you agree or a D if you disagree. As you read this chapter, see if you change your mind about any of the statements. Before You Read Statements After You Read 1. Waves carry matter as they travel from one place to another. 2. Sound waves can travel where there is no matter. 3. Waves that carry more energy cause particles in a material to move a greater distance. 4. Sound waves travel fastest in gases such as air. 5. When light waves strike a mirror, they change direction. 6. Light waves travel at the same speed in all materials. What have you learned? After you read each lesson, return to this worksheet to see if you have changed your mind about any of the statements related to that lesson. Place a C after each statement that is correct or an I for those that are incorrect. Waves 1

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9 Quick Vocabulary Lesson 1 compression region of a longitudinal wave where the particles in the medium are closest together crest highest point on a transverse wave electromagnetic wave can travel through empty space and through matter Lesson 2 amplitude maximum distance particles in a medium move from their rest position as waves pass through the medium frequency number of wavelengths that pass by a point each second wavelength distance from one point on a wave to the same point on the next wave energy ability to cause change longitudinal wave makes the particles in a medium move parallel to the direction of the wave mechanical wave travels only through matter medium material in which a mechanical wave travels rarefaction region of a longitudinal wave where the particles are farthest apart transverse wave disturbance is perpendicular to the direction of the wave trough lowest point on a transverse wave wave disturbance that transfers energy from one place to another Waves 3

10 Quick Vocabulary Lesson 3 absorption transfer of energy by a wave to the medium through which it travels constructive pertaining to building or putting parts together to make a whole diffraction change in direction of a wave when it travels by the edge of an object or through an opening interference waves that overlap combine to form a new wave law of reflection angle of incidence equals angle of reflection normal perpendicular to or forming a right angle with a line or plane reflection bouncing of a wave off a surface refraction wave changes direction, because its speed changes transmission passage of light through an object 4 Waves

11 Student Lab/Activity Safety Form Teacher Approval Initials Date of Approval Student Name: Date: Lab/Activity Title: Carefully read the entire lab, and answer the following questions. Return this completed and signed safety form to your teacher to initial before you begin the lab/activity. 1. Describe what you will be doing during this lab/activity. Ask your teacher any questions you have regarding the lab/activity. 2. Will you be working alone, with a partner, or with a group? (Circle one.) 3. What safety precautions should you take while doing this lab/activity? 4. Write any steps in the procedure, additional safety concerns, or lab safety symbols that you do not understand. Student Signature Waves 5

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13 Lesson 1 What are waves? Student Labs and Activities Page Appropriate For: Launch Lab 8 all students Content Vocabulary ELL 9 all students Lesson Outline ELL 10 all students MiniLab 12 all students Content Practice A 13 AL AL AL Content Practice B 14 AL OL BL School to Home 15 all students Key Concept Builders 16 AL AL AL Enrichment 20 all students Challenge 21 AL AL BL Assessment Lesson Quiz A 22 AL AL AL Lesson Quiz B 23 AL OL BL Teacher Support Answers (with Lesson Outlines) T2 AL Approaching Level OL On Level BL Beyond Level ELL English-Language Learner Teacher evaluation will determine which activities to use or modify to meet any ELL student s proficiency level. Waves 7

14 Launch Lab LESSON 1: 20 minutes How can you make waves? Oceans, lakes, and ponds aren t the only places you can find waves. Can you create waves in a cup of water? Procedure 1. Read and complete a lab safety form. 2. Add water to a clear plastic cup until it is about two-thirds full. Place the cup on a paper towel. 3. Explore ways of producing water waves by touching the cup. Do not move the cup. 4. Explore ways of producing water waves without touching the cup. Do not move the cup. Data and Observations Think About This 1. How did the water s surface change when you produced water waves in the cup? 2. Key Concept What did the different ways of producing water waves have in common? 8 Waves

15 Content Vocabulary LESSON 1 What are waves? Directions: In this word search puzzle, find and circle the 11 terms listed below. Then write each term on the line before its definition. compression crest electromagnetic wave energy longitudinal wave mechanical wave medium rarefaction transverse wave trough wave C O M P R E S S I O N D E T L M C W R E L E C T R O M A G N E T I C W A V E T I N O B Q M S P I M U P R U F B B K R M E D I U M L R A R E F A C T I O N O C R E S T R N S V U O M N A E W L I U S G T O M E C H A N I C A L W A V E G Z Y G A P T U T M L P R R X U V S L H I T R A N S V E R S E W A V E E I H L V L O N G I T U D I N A L W A V E Y 1. ability to cause change 2. region of a longitudinal wave where the particles are farthest apart 3. travels through empty space and through matter 4. disturbance that transfers energy but not matter 5. highest point on a transverse wave 6. lowest point on a transverse wave 7. region of a longitudinal wave where the particles in the medium are closest together 8. makes particles in a medium move parallel to the direction that the wave is traveling 9. a material in which a mechanical wave travels 10. when the disturbance is perpendicular to the direction the wave travels 11. travels only through matter Waves 9

16 Lesson Outline LESSON 1 What are waves? A. What are waves? 1. A(n) is a disturbance that transfers energy from one place to another without transferring matter. 2. Waves transfer energy from the source of the energy. 3. Waves transfer energy without transferring. 4. Waves transfer energy by pushing and on neighboring particles. B. Mechanical Waves 1. A wave that can travel only through is a mechanical wave. 2. The material in which a mechanical wave travels is called a(n). 3. A(n) wave is a wave in which the disturbance is moving at right angles, or perpendicular, to the direction the wave travels. 4. The points on a transverse wave are crests. The points on a transverse wave are troughs. 5. A longitudinal wave makes particles move to the direction that the wave is traveling. 6. The regions of a longitudinal wave where the particles in the medium are closest together are. The regions of a longitudinal wave where the particles are farthest apart are. 7. A vibrating object, such as a drum, is the source of that produces mechanical waves. a. Each makes a wave. b. After an object stops vibrating, continue to move. C. Types of Mechanical Waves 1. All mechanical waves travel only through. 2. Sound waves are waves that can travel through solids, liquids, and gases. 10 Waves

17 Lesson Outline continued 3. Water waves are a combination of waves and longitudinal waves. 4. waves are produced when parts of Earth s upper layers move along a fault. D. Electromagnetic Waves 1. An electromagnetic wave can travel through a(n) and through matter. 2. The type of electromagnetic waves given off by an object depends mainly on the of the object. 3. The Sun s carry radiant energy. Waves 11

18 MiniLab LESSON 1: 15 minutes How do waves travel through matter? When a wave travels through matter, energy transfers from particle to particle. How do particles move in different types of waves? Procedure 1. Read and complete a lab safety form. 2. Tie a piece of yarn around a rope. Stretch the rope on the floor between you and a partner. Make a transverse wave by moving the rope side to side on the floor. Observe how the yarn moves. 3. Tie a piece of yarn around one coil near the middle of a metal spring toy. Sharply push one end of the spring toy forward. Observe how the yarn moves. Data and Observations Analyze and Conclude 1. Compare the motion of the yarn on the rope and on the spring. 2. Key Concept How did the particles in each medium move as the wave passed? 12 Waves

19 Content Practice A LESSON 1 What are waves? Directions: Work with a partner to list the types of mechanical and electromagnetic waves in the space provided. Mechanical (Transverse and Longitudinal) 1. Types include: 2. Types include: Electromagnetic Waves Directions: Answer each question in the space provided. Mechanical Waves Electromagnetic Waves What do they carry? How are they produced? Through which media can they move? Where do they transfer energy? What do they not transfer? Waves 13

20 Content Practice B LESSON 1 What are waves? Directions: Answer the questions below. Then find and circle those ten terms in the word search puzzle. All About Waves S D A Q H F P W Z D U S I J T W U I G F S E S K S M B X B E E Z G V R S E N A N Z D V J G N U X G I X N F E A A D W S B B I T A C Z K C S O L I D S R J J B E Z Q F O P W X G M B J T I L Y E F A Z S M K X P F Q R I I H I S Z H Q F B R T V S C Z V X S C E N V F D F Z U A W B J P H O R L X W O J T M O I M A I C W J A H Y Y O E A T Z Y L A Q U X O U T F C J V I B X V S F G W U C W Q P J C I E B E M H Y E I Y T R W N T K I N L J O M U J T I S O K W I S T P K R L S P U N R V G D X G V C C Z B E U T R O U G H S D S V C D S E V A W D N U O S E K A L Y H R L M T 1. Through which type of media can mechanical waves move? 2. What are the high and low points of transverse waves called? 3. What are the opposites of compressions in a longitudinal wave? 4. What are three types of mechanical waves? 5. Which medium can electromagnetic waves move through that mechanical waves cannot? 14 Waves

21 School to Home LESSON 1 What are waves? Directions: Use your textbook to answer each question or respond to each statement. 1. What is the definition of a wave? 2. Write a description that you can use to teach your learning partner about transverse waves. 3. Write a description that you can use to teach your learning partner about longitudinal waves. 4. Use the table below to classify the following types of waves as mechanical waves or electromagnetic waves. infrared light radio seismic sound ultraviolet water Mechanical Waves Electromagnetic Waves Waves 15

22 Key Concept Builder LESSON 1 What are waves? Key Concept What is a wave? Directions: On the line before each definition, write the letter of the term that matches it correctly. Each term is used only once. 1. the back-and-forth or up-and-down movement of an object 2. makes the particles in a medium move parallel to the direction of the wave 3. the regions of a longitudinal wave where the particles are farthest apart 4. longitudinal waves that travel through solids, liquids, and gases 5. the highest points on a transverse wave 6. waves that travel through Earth 7. a wave that can travel through empty space and through matter 8. a wave in which the disturbance is perpendicular to the direction the wave travels 9. a disturbance that transfers energy from one place to another without transferring matter 10. a wave that can travel only through matter 11. energy carried by electromagnetic waves 12. the lowest points on a transverse wave 13. the regions of a longitudinal wave where the particles in the medium are closest together 14. a combination of transverse waves and longitudinal waves that travels along the surface of water A. transverse waves B. sound waves C. energy D. compressions E. vibration F. seismic waves G. mechanical wave H. rarefactions I. crests J. water waves K. troughs L. radiant energy M. wave N. longitudinal waves O. electromagnetic wave 15. the ability to cause change 16 Waves

23 Key Concept Builder LESSON 1 What are waves? Key Concept How do different types of waves make particles of matter move? Directions: Use the diagram on the left to answer each question. Wave direction 1. What is a wave? 2. What is the medium of this wave? 3. From which side of the illustration does the wave originate? 4. To which side of the illustration does the wave move? 6. Why doesn t the raft move in the same direction as the wave? 5. To which side of the illustration does the raft move? 7. Draw a diagram below to show how energy transfers when a raindrop hits water in a pond. Waves 17

24 Key Concept Builder LESSON 1 What are waves? Key Concept How do different types of waves make particles of matter move? Directions: Label each wave type as transverse or longitudinal. Then provide an example of that type of wave. Crest Direction wave moves Rest position Direction rope moves Trough 1. Wave type: 2. Example: 3. Wave type: 4. Example: Motion of coil Rarefaction Wave motion Compression 18 Waves

25 Key Concept Builder LESSON 1 What are waves? Key Concept Can waves travel through empty space? Directions: Work with a partner to complete the chart below. 1. An electromagnetic wave is. Type of Wave Evidence of Wave Presence Directions: Write four questions and answers for electromagnetic waves. Questions Example: What are five types of electromagnetic waves? Answers Examples: light, radio, microwaves, infrared, ultraviolet 10. Waves 19

26 Enrichment LESSON 1 The Electromagnetic Spectrum An electromagnetic (EM) wave can travel through a vacuum as well as through matter. EM waves can be classified by their wavelength and frequency. This classification is called the electromagnetic spectrum. The electromagnetic spectrum includes EM waves that have wavelengths from thousands of meters to a fraction of the size of an atom. EM waves that have the longest wavelengths are called radio waves. EM waves that have the shortest wavelengths are called gamma rays. Radio waves have long wavelengths and low frequencies. The wavelengths of radio waves range from hundreds of meters to about 1 mm. They are used to transmit signals for AM and FM radios, television, MRI, and wireless networking. A radio station broadcasts radio waves that travel in all directions from an antenna. Microwaves have shorter wavelengths and higher frequencies than radio waves. In microwave ovens, microwaves cause water molecules inside the food to move faster, increasing the food s temperature. Infrared rays have shorter wavelengths and higher frequencies than microwaves Applying Critical-Thinking Skills Directions: Respond to each statement. 1. Describe the relationship between frequency and wavelength. 2. Infer what the prefixes infra and ultra mean. and radio waves. Infrared waves are given off by the Sun, stars, planets, living things, and other objects. Warmer objects emit more infrared waves than cooler objects. Cameras that detect infrared waves can make images of objects even in the dark. Visible light is the range of wavelengths and frequencies that humans can see. If EM waves that have a frequency in this region of the EM spectrum reflect off an object and strike your eyes, you can see the object. Ultraviolet waves have shorter wavelengths and higher frequencies than visible light. UV waves are produced by the Sun, and some exposure is beneficial to humans. Too much exposure to UV waves from the Sun can cause sunburn. X-rays have very short wavelengths and very high frequencies. X-rays are used in medicine to see through soft tissue and get pictures of bone. Gamma rays are the EM waves that have the shortest wavelengths and highest frequencies. They are used in radiation therapy to kill cancer cells in the body. 3. Analyze the relationships among the amount of energy produced, wavelength, and frequencies of electromagnetic waves. 20 Waves

27 Challenge LESSON 1 Mapping Infrared Radiation Suppose you have an infrared camera and film that detects differences in temperature. Create a map of a room or an outdoor area containing living things and other objects as it might look in a picture taken with the infrared camera. Use the temperatures below as reference points. human = 36.6 C-37.3 C cat = 38.1 C-39.2 C dog = 38.3 C-38.9 C parrot = 39.4 C-41.1 C Estimate the temperatures of walls, windows, furniture, and other objects. Tape a thermometer to the object with clear tape, or formulate an estimation scale to compare how the temperature of an object feels compared to the temperature of your hand. Complete your map by assigning a different color to each temperature range. Use those colors to map the infrared radiation being given off. Waves 21

28 Lesson Quiz A LESSON 1 What are waves? Multiple Choice Directions: On the line before each question, write the letter of the correct answer. 1. What does a wave transfer? A. power B. matter C. energy 2. Which type of wave is a radio wave? A. mechanical B. longitudinal C. electromagnetic 3. Which type of wave has rarefactions and compressions? A. transverse B. longitudinal C. electromagnetic Matching 4. Which type of wave is produced by movement at cracks in Earth s upper layer? A. seismic B. ultraviolet C. electromagnetic 5. What is the name for the lowest point on a transverse wave? A. crest B. trough C. wavelength Directions: On the line before each definition, write the letter of the term that matches it correctly. Each term is used only once. 6. the highest point on a transverse wave 7. Waves do not transfer this. 8. Sunlight produces these. 9. type of wave that travels only through matter 10. Waves in which the disturbance is perpendicular to the direction the waves travel. A. matter B. mechanical waves C. electromagnetic waves D. transverse waves E. crest 22 Waves

29 Lesson Quiz B LESSON 1 What are waves? Completion Directions: On each line, write the term that correctly completes each sentence. 1. All waves transfer as they travel. 2. waves can move without a medium. 3. are areas of longitudinal waves in which particles are closest together. 4. waves are produced by movement at cracks in Earth s upper layer. 5. The lowest point on a transverse wave is the. Short Answer Directions: Respond to each statement on the lines provided. 6. Define the terms crest and trough and discuss how they relate to the wavelength of a wave. 7. Explain how a mechanical wave moves without moving or transferring matter. 8. Support or refute this statement: All energy from the Sun is visible. Answer in terms of the waves that make up sunlight. 9. State one way in which transverse waves differ from longitudinal waves. Waves 23

30 Lesson 2 Wave Properties Student Labs and Activities Page Appropriate For: Launch Lab 25 all students Content Vocabulary ELL 26 all students Lesson Outline ELL 27 all students MiniLab 29 all students Content Practice A 30 AL AL AL Content Practice B 31 AL OL BL Math Skills 32 all students School to Home 33 all students Key Concept Builders 34 AL AL AL Enrichment 38 all students Challenge 39 AL AL BL Skill Practice 40 all students Assessment Lesson Quiz A 42 AL AL AL Lesson Quiz B 43 AL OL BL Teacher Support Answers (with Lesson Outlines) T4 AL Approaching Level OL On Level BL Beyond Level ELL English-Language Learner Teacher evaluation will determine which activities to use or modify to meet any ELL student s proficiency level. 24 Waves

31 Launch Lab LESSON 2: 20 minutes Which sounds have more energy? Some sounds are loud and others are soft. What is the difference between loud and soft sounds? Procedure 1. Read and complete a lab safety form. 2. Place a bowl of water over a sheet of white paper. 3. Strike a tuning fork gently on your hand so it makes a soft sound and then quickly place its prongs in the bowl of water. Remove the tuning fork. 4. Strike the tuning fork sharply on your hand so it makes a loud sound and then quickly place its prongs in the bowl of water. Data and Observations Think About This 1. Contrast the waves made by the tuning fork in steps 3 and In which step did the tuning fork transfer more energy to the water? Explain your answer. 3. Key Concept How are the loudness of the sounds and the vibrations of the tuning fork related? Waves 25

32 Content Vocabulary LESSON 2 Wave Properties Directions: Unscramble each term. queenfryc dilutepam glewnevath Directions: On the line before each definition, write the term from above that matches it correctly. 1. the number of waves that pass by a point each second 2. the maximum distance the particles in a medium move from their rest position as the wave passes through the medium 3. the distance from one point on a wave to the same point on the next wave 26 Waves

33 Lesson Outline LESSON 2 Wave Properties A. Amplitude and Energy 1. The of a wave is the maximum distance that the particles in a medium move from their rest position as the wave passes. 2. For any wave, the larger the amplitude is, the more the wave carries. 3. waves have crests and troughs. The of these waves is the distance from the rest position to the top of a crest or the bottom of a trough. 4. The amplitude of a(n) wave depends on the distance between particles in the compressions and rarefactions. When the amplitude of these waves increases, the particles in the medium get closer together in the and farther apart in the. B. Wavelength 1. is the distance from one point on a wave to the same point on the next wave. 2. In a(n) wave, a wavelength is the distance from one crest to the next crest or from one trough to the next trough. 3. In a(n) wave, a wavelength is the distance from one compression to the next compression or from one rarefaction to the next rarefaction. C. Frequency 1. The of a wave is the number of wavelengths that pass by a point each second. 2. Each single of an object produces one wavelength. 3. The unit for frequency is the, abbreviated Hz. 4. As the frequency of a wave increases, the wavelength. D. Wave Speed 1. Wave speed depends on the type of wave, the, and the medium the wave is traveling through. 2. Mechanical waves, such as sound, usually travel fastest in solids and slowest in. Waves 27

34 Lesson Outline continued 3. Electromagnetic waves travel fastest through a vacuum and slowest through. 4. You can calculate the speed of a wave by multiplying its wavelength by its. 28 Waves

35 MiniLab LESSON 2: 20 minutes How are wavelength and frequency related? Waves traveling in a material can have different frequencies and wavelengths. Is there a relationship between the wavelength and frequency of a wave? Procedure 1. Read and complete a lab safety form. 2. With a partner, stretch a piece of rope, approximately 2 3 m long, across a lab table or the floor. Move your hand side to side while your partner holds the other end of the rope in place. Observe the wavelength. 3. Move your hand side to side faster. Observe the wavelength. Data and Observations Analyze and Conclude 1. Explain When was the frequency of the wave higher? Lower? 2. Key Concept How are wavelength and frequency related? Waves 29

36 Content Practice A LESSON 2 Wave Properties Directions: Label this diagram by writing the letter in front of each term from the word bank on the correct line. Some terms may not be used, and some may be used more than once. Transverse Wave A. amplitude B. compression C. crest D. rarefaction E. rest position F. trough G. wavelength Directions: Complete this paragraph by choosing terms from the word bank above and writing them in the correct spaces. Some terms may not be used, and some may be used more than once. In a transverse wave, a(n) (7.) is the distance from one (8.) to the next crest or from one (9.) to the next trough. In a longitudinal wave, the (10.) is the distance from one (11.) to the next compression or from one (12.) to the next rarefaction. 30 Waves

37 Content Practice B LESSON 2 Wave Properties Directions: Answer each question by listing a word or phrase next to each bullet. Question Answer 1. What happens to the energy carried in a transverse wave as the amplitude increases? 2. What happens to the particles in a longitudinal wave as the amplitude increases? 3. What unit is used to measure wavelength? 4. What does each single vibration of an object produce? 5. In which units are frequencies measured? 6. What happens to wavelength as the frequency of a wave increases? 7. What two factors are used to determine the frequency of waves? 8. What does the speed of a wave depend on? 9. What two factors are multiplied to determine wave speed? Waves 31

38 Math Skills LESSON 2 Use a Simple Equation The speed of a wave depends on its wavelength and its frequency. This can be shown by the equation below, where s = wave speed (in m/s), f = frequency (in Hz), and λ = wavelength (in m). s = f λ You can rearrange the equation to solve for either of the other variables. For example: f = s λ λ = _ s f A sound wave has a frequency of 400 Hz and a wavelength of 0.6 m. What is the speed of the wave? Step 1 Identify the given variables. f = 400 Hz, λ = 0.6 m Step 2 Identify the equation that is needed to solve for the unknown variable. s = f λ Step 3 Substitute the known values to solve the equation. s = s = 240 m/s Practice 1. A sound wave has a frequency of 627 Hz and a wavelength of 3.25 m. What is the speed of the wave? 2. A sound wave is traveling at 331 m/s and has a frequency of 126 Hz. What is the wavelength? 3. A sound wave is traveling at 3,810 m/s and has a wavelength of 8 m. What is the frequency of the wave? 4. A sound wave is traveling at 6,420 m/s and has a frequency of 600 Hz. What is the wavelength? 32 Waves

39 School to Home LESSON 2 Wave Properties Directions: Use your textbook to answer each question or respond to each statement. 1. Make a sketch of transverse waves in the space below. Label a crest and a trough. Label the amplitude and wavelength. 2. Make a sketch of longitudinal waves in the space below. Label a compression and a rarefaction. Label the wavelength. 3. Which wave has more energy a wave that has a small amplitude or a wave that has a large amplitude? 4. For waves moving at the same speed, which one has a greater frequency a wave that has a short wavelength or a wave that has a long wavelength? 5. What is the speed of a wave that has a frequency of 600 Hz and a wavelength of 2 m? Show the steps you used to solve this problem. 6. What is the frequency of a wave that has a speed of 1,500 m/s and a wavelength of 3 m? Show the steps you used to solve this problem. Waves 33

40 Key Concept Builder LESSON 2 Wave Properties Key Concept What are properties of waves? Directions: On the line before each definition, write the letter of the term that matches it correctly. Each term is used only once. 1. the maximum distance particles in a medium move from their rest position as a wave passes 2. the distance from one point on a wave to the same point on the next wave 3. the unit for frequency; also the same as 1/s A. hertz (Hz) B. frequency C. amplitude D. wavelength 4. the number of wavelengths that pass by a point each second Directions: On each line, write the term from the list above that correctly completes each sentence. 5. The distance from the crest of a wave to the next crest is its. 6. When the of a longitudinal wave increases, the particles in the medium move closer together and farther apart. 7. The of a wave is the same as the number of vibrations a vibrating object makes each second. 8. A wave that has a frequency of 4 has four wavelengths that pass a point every second. 34 Waves

41 Key Concept Builder LESSON 2 Wave Properties Key Concept How are the frequency and the wavelength of a wave related? Directions: Answer each question on the lines provided. 1. How is frequency in a transverse wave similar to frequency in a longitudinal wave? 2. How are the frequency and the wavelength of a wave related? Directions: Create two drawings to show the relationship between frequency and wavelength. Longer Wavelengths Shorter Wavelengths Waves 35

42 Key Concept Builder LESSON 2 Wave Properties Key Concept How are the frequency and the wavelength of a wave related? Directions: Complete each statement on the lines provided. Transverse Wave Crest Rest position Wavelength Amplitude Trough Amplitude 1. A wave that has smaller amplitude than another carries less. 2. Amplitude is the maximum distance that the particles in a medium. 3. A wavelength of a wave is the distance from. 4. As the frequency of a wave increases, the wavelengths. 5. The frequency of a wave is the number of. 6. The frequency of a wave is related to how. 7. Changing the frequency of waves also changes. 8. The frequency of a wavelength can be calculated by. 36 Waves

43 Key Concept Builder LESSON 2 Wave Properties Key Concept What affects wave speed? Directions: Answer each question to complete the chart below. Question Answer What is true about the speed of waves as they travel through different materials? 1. What is usually true about the speed of mechanical waves in solids compared with their speed in gases? What is usually true about the relationship between the speed mechanical waves travel and the temperature of the medium? What happens to the speed of electromagnetic waves as they travel through different media? Where do electromagnetic waves move fastest? Where do electromagnetic waves move slowest? Directions: Answer the question in the space provided. Then diagram your explanation. 7. Why do you see the flash of lightning before you hear the thunder during a storm? Diagram: Waves 37

44 Enrichment LESSON 2 Wave Properties Radio waves are electromagnetic (EM) waves that transfer energy without traveling through a medium. Although radio waves are low-energy waves, they travel at the speed of light. Radio waves are used to transmit broadcasts from radio and television stations, to operate a variety of household and commercial devices, and to gather information from outer space using radio telescopes. To broadcast information by radio waves, a radio station converts sound into an electric current. The current produces waves, and sound information is encoded into the waves by varying the waves amplitude or frequency. An antenna sends the radio waves outward in all directions. Radio sets receive radio waves and convert them into an electric current and then into sound. Changing the amplitude or frequency is called modulation. Waves with amplitude modulation, called AM radio, are transmitted into space using an antenna at an AM radio station. FM radio stations and hundreds of other wireless technologies, such as cordless phones, cell phones, garage-door openers, microwave ovens, and GPS receivers, use frequency modulation. Because AM waves reflect off a layer of the atmosphere called the ionosphere, they can travel farther than FM waves, which travel Applying Critical-Thinking Skills Directions: Respond to each statement. through the ionosphere. Advantages of FM are that more information can be encoded in the wave, that there is virtually no static, and that music sounds better. An example of a scientific use of radio waves is the radio telescope. These telescopes receive naturally occurring radio emissions from distant galaxies, stars, pulsars, quasars, and possible black holes. All radio telescopes have two basic components a large radio antenna and a sensitive radio receiver. The most common type has a large dish-shaped parabolic antenna, which collects incoming radio waves and reflects them to a smaller antenna. This small antenna transfers the incoming signal to the radio receiver. The signals are recorded on tape and read by a computer that combines the signals to create an image of the source of the radio waves. Some radio telescopes are arranged in groups. The VLA (Very Large Array) consists of 27 radio telescopes, each 25 meters in diameter, that are mounted on railroad tracks and electronically linked by computers. They operate together, like a single telescope with a diameter of 47 m. The VLBA (Very Long Base Array) is an array of single telescopes that are located in different parts of the world but work together. This array is equal to a telescope that is almost as large as Earth itself. 1. Give examples of two modulated waves and describe how they got that way. 2. State a benefit of grouping radio telescopes in very large and very long arrays. 38 Waves

45 Challenge LESSON 2 Radio Broadcast Coverage Sioux Falls Scale 1: 3,250,184 km KRSW KWIT Sioux City KIWR Omaha Worthington KLSEFM KTPR WHHI KUNY KLCD Mason CIty KUNI Plattesville KHKE Fort Dodge KBBG Dubuque Waterloo WOI-FM KCCKFM KSUI Cedar Rapids KJMC KDPS Des Moines KXCV Maryville Rochester Iowa City Davenport Fort Madison WIUW WVIK Above is a map of FM coverage from radio frequency towers in and near the state of Iowa. 1. Calculate an approximate percentage of the land area in Iowa that does not have FM radio coverage. (Measure the diameters of the circles and calculate the areas and partial areas of all circles providing any coverage in Iowa. Subtract the area of coverage from the total area of Iowa. Use these figures to calculate the approximate percentage.) 2. Design a study to compare the percentage of FM noncoverage in your county or region with the same percentage of FM noncoverage in the state of Iowa. Organize the plan for your study into these sections Question, Materials, Methods, Data Collection, Data Analysis, Conclusion, New Questions. Data-collection methods might include: a citizen survey (sample question: Have you ever lost FM reception while you were driving in certain areas?) a field survey of the location of radio transmission towers interviewing radio-station personnel by phone, by mail, or in person. (Create a list of questions to ask during every interview.) In the Methods section, describe how you will use the data collected. Waves 39

46 Skill Practice Model LESSON 2: 25 minutes How are the properties of waves related? All waves have amplitude, wavelength, and frequency. The properties of a wave are related and also determine the amount of energy the wave carries. Learn It Scientists create models to study many objects and concepts that are difficult to observe directly. You used a coiled spring toy in previous labs to model a longitudinal wave. In this lab, you will use the same toy to model transverse waves. Try It 1. Read and complete a lab safety form. 2. With a partner, use masking tape to secure two meter tapes to the floor, creating x- and y-axes. 3. With your partner, stretch the coiled spring toy across the tape representing the x-axis. Generate a transverse wave by moving the toy back and forth on the floor. Try to be as steady and even as possible to generate consistent waves. 4. Using the tape on the y-axis, measure and record the amplitude of the wave. Record it in your data table below. 5. Using the tape representing the x-axis, measure the wavelength of the wave. Record your measurement. 6. Using a stopwatch, count and record the number of crests or troughs that cross the y-axis in 10 seconds. 7. Repeat steps 2 5 for waves with different properties by moving the toy faster and slower. Trial Amplitude (cm) Wavelength (cm) Number of Vibrations in 10 seconds Frequency (Hz) 40 Waves

47 Skill Practice continued Apply It 8. Calculate below the frequency of each wave generated and record it in your data table. 9. Which wave transferred the most energy? Explain. 10. Key Concept What happened to the frequency and wavelength of the waves when you moved the spring toy faster and slower? How are frequency and wavelength related? Waves 41

48 Lesson Quiz A LESSON 2 Wave Properties Multiple Choice Directions: On the line before each question, write the letter of the correct answer. 1. What is the distance from one compression to the next in a longitudinal wave? A. its amplitude B. its frequency C. its wavelength 2. If the amplitude of a wave increases, what also increases? A. speed B. energy C. frequency 3. How is wave frequency measured? A. wavelengths per meter B. wavelengths per second C. wavelengths per centimeter True or False 4. If the frequency of a wave increases, what decreases? A. speed B. amplitude C. wavelength 5. On a longitudinal wave, in which areas are particles farthest apart? A. crests B. troughs C. rarefactions Directions: On the line before each statement, write T if the statement is true or F if the statement is false. 6. The unit of measurement for wave frequency is hertz. 7. The speed of a wave is frequency multiplied by amplitude. 8. Different types of waves travel at different speeds at different temperatures. 42 Waves

49 Lesson Quiz B LESSON 2 Wave Properties Matching Directions: On the line before each definition, write the letter of the term that matches it correctly. Not all terms are used. 1. maximum distance particles move from their resting position 2. distance from one point on a wave to the same point on the next wave 3. number of wavelengths per second 4. frequency wavelength 5. unit for frequency A. frequency B. rarefaction C. amplitude D. wave speed E. wavelength F. hertz G. transverse wave Short Answer 6. regions of a longitudinal wave where particles are farthest apart Directions: Answer each question or respond to each statement on the lines provided. 7. Suppose you made a wave by pinching the coils of a spring together and then letting go. A few seconds later, the spring s coils aren t as far apart in its compressions or as far apart in its rarefactions. What has happened to the wave, and what type of wave does this model? 8. Explain what happens to a wave s speed if the wavelength stays the same but the frequency is increased. 9. Predict how warming a piece of metal would change the way mechanical waves travel through it. Waves 43

50 Lesson 3 Wave Interactions Student Labs and Activities Page Appropriate For: Launch Lab 45 all students Content Vocabulary ELL 46 all students Lesson Outline ELL 47 all students MiniLab 49 all students Content Practice A 50 AL AL AL Content Practice B 51 AL OL BL Language Arts Support 52 all students School to Home 54 all students Key Concept Builders 55 AL AL AL Enrichment 59 all students Challenge 60 AL AL BL Lab A 63 AL AL AL Lab B 66 AL OL BL Lab C 69 AL AL BL Chapter Key Concepts Builder 70 AL AL AL Assessment Lesson Quiz A 61 AL AL AL Lesson Quiz B 62 AL OL BL Chapter Test A 71 AL AL AL Chapter Test B 74 AL OL AL Chapter Test C 77 AL AL BL Teacher Support Answers (with Lesson Outlines) T5 AL Approaching Level OL On Level BL Beyond Level ELL English-Language Learner Teacher evaluation will determine which activities to use or modify to meet any ELL student s proficiency level. 44 Waves

51 Launch Lab LESSON 3: 20 minutes What happens in wave collisions? You might have seen ripples on a water surface spreading out from different points. As the water waves reach each other, they collide. Do waves change after they collide? Procedure 1. Read and complete a lab safety form. 2. Stretch a metal coiled spring toy about cm between you and a partner. 3. Make a wave by grabbing about five coils at one end and then releasing them. Record your observations in your Science Journal. 4. Make waves at both ends of the spring with your partner. Make waves that appear much different from each other so you can distinguish them easily. Then release them at the same time. Observe and record how each wave moves before, during, and after the collision. Think About This 1. Describe how the two waves moved after the coils were released. 2. Key Concept How were the two waves affected by their collision? Waves 45

52 Content Vocabulary LESSON 3 Wave Interactions Directions: Use the clues and the terms listed below to complete the puzzle. Some terms may not be used. NOTE: There is no empty square in the puzzle between the words of two-word terms. absorption constructive diffraction interference law of reflection normal reflection refraction transmission Across 1. overlapping waves combine to make a new wave 3. change in wave s direction when it travels by the edge of an object or through an opening 5. perpendicular to a line or plane 8 Clues Down 2. when waves bounce off a material s surface 4. the angle of incidence equals the angle of reflection 6. transfer of energy by a wave to the medium through which it travels 7. when a wave changes direction because its speed changes 8. passage of light through an object 46 Waves

53 Lesson Outline LESSON 3 Wave Interactions A. Interaction of Waves with Matter 1. Absorption is the transfer of by a wave to the medium through which it travels. a. One factor that affects the amount of energy absorbed is the in which a material moves. b. All materials absorb waves. 2. is the passage of light through an object. 3. is the bouncing of a wave off a surface. a. Objects that reflect all visible light appear. b. Objects that do not reflect any visible light appear. B. The Law of Reflection 1. All types of waves can be when they hit a surface. 2. The angle at which a wave hits a surface is the at which it bounces off the surface. a. The normal is an imaginary line that is to a surface. b. The angle of is equal to the angle between the normal and an incoming wave. c. The angle of is equal to the angle between the normal and an outgoing wave. 3. The angle of incidence and the angle of reflection are. This rule is called the. C. Refraction 1. Refraction occurs when a wave changes because its speed changes. 2. The greater the change in speed is, the the wave changes direction. D. Diffraction 1. The change in direction of a wave when it travels by the edge of an object or travels through an opening is called. Waves 47

54 Lesson Outline continued 2. waves spread out as they travel through a doorway because their wavelengths are roughly the same width as the doorway. 3. The wavelengths of waves are more than a million times smaller than the width of a doorway. As a result, these waves do not spread out as they travel through a doorway. E. Interference 1. Interference occurs when waves to form a new wave. 2. interference occurs when a crest overlaps a crest or a trough overlaps a trough. 3. interference occurs when a crest overlaps a trough. 4. A(n) wave can form when two waves with the same wavelength overlap while they are traveling in opposite directions. 48 Waves

55 MiniLab LESSON 3: 20 minutes How can reflection be used? Light waves, like all waves, obey the law of reflection. By using mirrors, you can see around corners. Procedure 1. Read and complete a lab safety form. 2. Place a small object on a table and stand a book vertically about 30 cm in front of the object. 3. Position a mirror vertically so an observer on the opposite side of the book from the object can see the object. Use modeling clay to prop up the mirror. 4. Use string to represent the path that light waves travel from the observer to the mirror and then to the object. Draw the outlined path in the Data and Observations section below. 5. Repeat steps 3 4 with two mirrors. Data and Observations Analyze and Conclude Key Concept How could three mirrors be used to see the object behind the book? Waves 49

56 Content Practice A LESSON 3 Wave Interactions Directions: Complete this diagram by choosing terms from the word bank and writing them in the correct spaces. absorption constructive destructive diffraction reflection refraction standing wave transmission Interactions 2. Interference 1. Wave interactions Directions: On each line, write the term that correctly completes each sentence. directions interact transferred 3. Some of the energy that waves carry can be to matter. How Waves Behave 4. Waves can change when they travel from one material to another. 5. Waves can each other. with 50 Waves

57 Content Practice B LESSON 3 Wave Interactions Directions: On the line before each phrase, write the letter of the phrase that completes each sentence. Each phrase is used only once. 1. Relative to waves, matter can 2. How much energy a material absorbs depends on the 3. When a material transmits waves, 4. Relative to the angle at which waves strike a surface, waves reflect 5. The two properties that are parts of refraction are 6. The two situations that can cause a wave to diffract are A. speed and direction. B. traveling by the edge of an object and traveling through an opening. C. type of wave and material. D. subtracts from the other. E. they travel through it. F. absorb, transmit, and reflect waves. G. they cancel each other. H. a new wave forms. I. the same angle. J. combine. 7. Where waves overlap, 8. During constructive interference, amplitudes 9. During destructive interference, one amplitude 10. If the overlapping waves have the same amplitude during destructive interference, Waves 51

58 Language Arts Support LESSON 3 Language-Usage Activity: Using Its and It s Language-Usage Note: Using Its and It s A common error in writing is using the word it s when the correct word is its. Its is the possessive form, meaning belonging to it. The model of the transverse wave did not match well with its actual shape. It s is a contraction of the words it and is. It is a type of electromagnetic wave. It s a type of electromagnetic wave. If you are unsure of which word to use, substitute it is in the sentence. If it makes sense, use it s. Directions: Circle the correct form of the term in each sentence. 1. What is a wave? (Its/It s) a disturbance that transfers energy without transferring matter. 2. Hitting a drum produces vibrations, which are mechanical waves, but (its/it s) hard to see the actual waves. 3. When a wave moves, (its/it s) movement does not transfer matter. 4. The highest points on a transverse wave are (its/it s) crests. 5. (Its/It s) called an electromagnetic wave if it can travel through a vacuum and through matter. 6. When an earthquake occurs, (its/it s) seismic waves shake the ground. 7. (Its/It s) fun to make longitudinal waves with a spring. 52 Waves

59 Language Arts Support LESSON 3 Word-Study Activity: Spelling Some word endings, although they are spelled differently, sound the same. The suffixes sion and tion are common noun endings. For example, say the words division and attraction. Their endings are spelled differently, but they are pronounced the same. Directions: Test your spelling. Study each word pair below. Which of the two versions is correct? On each line, write the letter A or B. A 1. absorption B absorpsion 2. transmistion transmission 3. reflection reflecsion 4. refraction refracsion 5. diffraction diffracsion 6. comprestion 7. rarefaction compression rarefacsion Waves 53

60 School to Home LESSON 3 Wave Interactions Did you know? Waves interact with matter and with other waves. Matter can absorb waves, transferring the energy of the wave to the matter. Matter can transmit waves, allowing the energy of waves to travel through. Matter also can reflect waves, which occurs when waves bounce off the surface of a material. Directions: Use your textbook to complete each activity. 1. Look around your home. Find a situation or location where waves are absorbed by matter. Remember that absorption occurs when waves do not travel through matter; instead waves transfer their energy to the matter. Describe how this situation or location demonstrates absorption. 2. Look around your home. Find a situation or location where matter transmits waves. Remember that transmission occurs when waves travel through a material. Describe how this situation or location demonstrates transmission. 3. Look around your home. Find a situation or location where waves are reflected by matter. Remember that reflection occurs when waves bounce off a material. Describe how this situation or location demonstrates reflection. 54 Waves

61 Key Concept Builder LESSON 3 Wave Interactions Key Concept How do waves interact with matter? Directions: On the line before each definition, write the letter of the term that matches it correctly. Each term is used only once. 1. transfer of energy by a wave to the medium through which it travels 2. passage of light through an object 3. bouncing of a wave off a surface 4. the term for a line that is perpendicular to a surface 5. the concept that the angle of incidence equals the angle of reflection 6. the angle between the direction of the reflected wave and the normal 7. the change in direction of a wave when it travels by the edge of an object or travels through an opening 8. what occurs when waves overlap and combine to form a new wave 9. what occurs when crests overlap crests and troughs overlap troughs 10. what occurs when a crest of one wave overlaps the trough of another wave 11. the name for a wavelength that is formed from combined waves 12. what occurs when a wave changes direction because its speed changes 13. the angle between the direction of the incoming wave and the normal A. refraction B. destructive interference C. normal D. absorption E. interference F. constructive interference G. transmission H. law of reflection I. reflection J. diffraction K. standing wave L. angle of reflection M. angle of incidence Waves 55

62 Key Concept Builder LESSON 3 Wave Interactions Key Concept How do waves interact with matter? Directions: Write the phrase that correctly completes each sentence. Then cite an example from everyday life. 1. Absorption occurs. Example: 2. Transmission occurs Example:. 3. Reflection occurs Example:. 4. Refraction occurs Example: 5. Diffraction is Example: 6. Interference occurs Example: Waves

63 Key Concept Builder LESSON 3 Wave Interactions Key Concept What are reflection, refraction, and diffraction? Directions: Add information to each chart to show how each set of wave interactions compare and how they contrast. How They Compare How They Contrast Reflection and Refraction How They Compare How They Contrast Reflection and Diffraction Refraction and Diffraction 5. How They Compare 6. How They Contrast Waves 57

64 Key Concept Builder LESSON 3 Wave Interactions Key Concept What is interference? Directions: Use the diagram showing interference to answer the question on the lines provided. Wave A Wave B 1. Does the diagram show constructive or destructive interference? Explain your answer. Wave A + Wave B Wave B Wave A Directions: Complete each if-then statement on the lines provided. 2. If the crests of two waves overlap, then 3. If the crest of one wave overlaps the trough of another wave, then 4. If two overlapping waves have the same amplitude, then 5. If a wave moves away from you and reflects off an object, then Waves

65 Enrichment LESSON 3 Wave Interactions Your level of enjoyment of a performance or program in a theater, concert hall, or auditorium depends upon the quality of the performers or speakers and the behavior of sound waves. These waves are affected by the size, shape, and other attributes of the room in which the event takes place. Acoustics is the study of the ways in which sound carries or can be heard within a particular enclosed space. New York City s Avery Fisher Hall at Lincoln Center, which opened in 1962, had so many acoustical problems that the inside was destroyed and replaced in One problem was that the floor was not tilted sufficiently; the height of the stage was not adequate and the audience seating was too flat. This meant that much of the sound created on the stage was absorbed by the bodies and clothing of people in the first few rows, leaving little residual sound for the ears of people who sat farther back. Complaints about the sound quality at the Walt Disney Concert Hall in Los Angeles stem from overly reflective surfaces. Wooden floors can add resonance to a hall. But when the wood is installed Applying Critical-Thinking Skills Directions: Respond to each statement. against concrete or in strong curved structures, as in the Disney hall, it becomes highly reflective, making sound waves bounce against the surfaces and creating a harsh acoustic environment. Coughing, whispering, and crumpling candy wrappers are amplified and heard throughout the hall. That is why most halls have carpeted floors that absorb audience noise. Acoustics experts and architects account for sound wave interactions such as reflection, diffraction, and absorption when they design group spaces. Good designs address the effects of the texture and shape of surfaces on reflection of sound waves. Hard materials such as concrete reflect most of the sound waves. Walls and materials that are made of softer materials such as fiberglass and acoustic tiles absorb more sound waves, which gives the room more pleasing acoustic qualities. Smooth walls have a tendency to direct sound waves in a specific direction. Rough walls tend to diffuse sound, reflecting it in many directions. This allows a listener to perceive sound from every part of the room, making it seem lively and full. 1. An important factor for a listener is the presence of diffuse reflectors (for lateral reflection) from the side walls of a concert hall. This effect envelops the listener in enjoyable sound. The traditional concert hall is a shoe box shape, which provides a large number of lateral reflections to the audience. Another popular structure, the fanshaped hall, has the advantage of being able to hold more people than the shoe box hall. Explain why the shoe box shape has an advantage over the fan-shaped hall. 2. One problem with the original design of Avery Fisher Hall was the failure to include enough convenient coatrooms. As a result, nearly every concertgoer carried his or her coat into the hall. Deduce the effect of these coats on the acoustical properties of the hall. Waves 59

66 Challenge LESSON 3 Acoustics Select three types of assembly or performance rooms that you can visit. Examine and analyze each room with respect to the interaction of sound waves with the room s structure and materials and determine the resulting acoustics. Examples of room types: auditorium cafeteria classroom concert hall gymnasium chapel library movie theater Draw a diagram of each room, including labels and descriptions of structures and materials that affect the interactions of sound waves and the resulting acoustics. If you have the opportunity, interview someone who uses the room frequently and has experienced its acoustical qualities. Summarize your analysis with a short statement comparing the causes and effects of the acoustical characteristics of each of the three rooms. 60 Waves

67 Lesson Quiz A LESSON 3 Wave Interactions Multiple Choice Directions: On the line before each question, write the letter of the correct answer. 1. What happens when waves slow down and change direction? A. refraction B. diffraction C. absorption 2. What is it called when two waves combine to form a new wave? A. reflection B. diffraction C. interference 3. What happens when the crests of two waves overlap to form a larger wave? A. diffraction interference B. destructive interference C. constructive interference Matching 4. What happens when the crest of one wave overlaps the trough of a different wave? A. diffraction interference B. destructive interference C. constructive interference Directions: On the line before each definition or diagram, write the letter of the term that matches it correctly. Each term is used only once A B 7. Light spreads out after it travels through a keyhole. A. refraction B. diffraction C. angle of reflection D. angle of incidence 8. A straw in a glass of water looks bent. Waves 61

68 Lesson Quiz B LESSON 3 Wave Interactions Completion Directions: On each line, write the term that correctly completes each sentence. 1. occurs when waves change direction, because their speed changes. 2. When two overlapping waves combine to form a completely new wave, has occurred. 3. occurs when the crest of one wave overlaps the crest of another wave. 4. occurs when the crest of one wave overlaps the trough of another wave. Short Answer Directions: Answer each question or respond to each statement on the lines provided. Normal Determine what the angle labeled 6 is called. 6. Determine what the angle labeled 7 is called. 7. A light wave changes direction as it travels through a chunk of glass into the air. Explain what property of waves this demonstrates. 8. Interpret You have two identical boxes, each with a different size hole in its lid. You place a kitchen timer inside each box and observe how well the timer is heard outside each box. What property of waves does this experiment test? 62 Waves

69 Lab A 55 minutes Measuring Wave Speed When you make a wave on a spring toy, the frequency is how many wavelengths pass a point per second. Wavelength is the distance between one point on the wave and the nearest point just like it. If you can measure the frequency and wavelength of a wave, you can figure out the wave speed. Ask a Question How can you determine the speed of a wave? Materials meter tapes (2) masking tape coiled spring toy twine, 0.25 m stopwatch or clock with second hand Safety Make Observations 1. Read and complete a lab safety form. 2. Lay the meter tapes on the floor, crossing each other to make x- and y-axes. Fasten the meter tapes in place with masking tape. 3. Tie a piece of twine around the last coil of the spring toy. 4. With a partner, stretch the spring toy along the x-axis. One person should hold one end of the spring toy at the y-axis. The other person should hold the twine at the end of the stretched spring. 5. One student creates a transverse wave by moving his or her hand back and forth along the y-axis at a constant rate. When the wave looks the same every time, another student times a 10-second period. At the same time, the third person counts the number of vibrations in 10 seconds. Record the number of vibrations in the data table on the next page. 6. As the student continues making the wave, another student should estimate the wavelength along the x-axis using the meter tape. Waves 63

70 Lab A continued 7. Calculate the frequency of the wave by dividing the number of wavelengths by the 10-second period when you timed the waves. Then calculate the wave speed using the equation: wave speed = frequency wavelength. 8. Repeat steps 5 through 7 using a different frequency. Trial Form a Hypothesis Number of Vibrations in 10 s Frequency (Hz) Wavelength (cm) Wave Speed (cm/s) 9. Form a hypothesis about the relationship between frequency and wavelength. Test Your Hypothesis 10. Choose a frequency that you did not use during Make Observations. Predict the wavelength for a wave with this frequency. 64 Waves

71 Lab A continued 11. Practice making a wave on the spring toy with your chosen frequency. Repeat steps 4 7 for this wave. Did your prediction of wavelength support your hypothesis? If not, revise your hypothesis and repeat steps 4 7. Lab Tips Keep the amplitude constant by moving the same distance on the y-axis in each vibration. Twenty vibrations in 10 s make a wave with a frequency of 2 Hz. Analyze and Conclude 12. Conclude How close was your prediction of wavelength compared to the actual measurement? 13. Think Critically What measurements were the most difficult to make? Suggest ways to improve on the method. 14. The Big Idea How did the wavelength, frequency, and wave speed change for the different waves that you created? Communicate Your Results Write a report explaining the steps you took in this lab. Include a table of the measurements you made. Be sure to describe sources of error in your measurements and ways that you might improve the accuracy of your experiment. Remember to use scientific methods. Make Observations Ask a Question Form a Hypothesis Test your Hypothesis Analyze and Conclude Communicate Results Waves 65

72 Lab B 55 minutes Measuring Wave Speed When you make a wave on a spring toy, the frequency is how many wavelengths pass a point per second. Wavelength is the distance between one point on the wave and the nearest point just like it. If you can measure the frequency and wavelength of a wave, you can determine the wave speed. Ask a Question How can you determine the speed of a wave? Materials meter tapes (2) masking tape coiled spring toy twine, 0.25 m stopwatch or clock with second hand Safety Make Observations 1. Read and complete a lab safety form. 2. Lay the meter tapes on the floor perpendicular to each other to make an x- and y-axis. Fasten them in place with masking tape. 3. Tie a piece of twine around the last coil of the spring toy. 4. With a partner, stretch the spring toy along the x-axis. One person should hold one end at the y-axis. The other person should hold the twine at the end of the outstretched spring. 5. One student creates a transverse wave by moving his or her hand up and down along the y-axis at a constant rate. When the wave is consistent, another student times a 10-second period while the third person counts the number of vibrations in 10 seconds. Record the number of vibrations in the data table on the next page. 6. As the student continues making the wave, another student should estimate the wavelength along the x-axis using the meter tape. 66 Waves

73 Lab B continued 7. Calculate the frequency of the wave. Then calculate the wave speed using the equation: wave speed = frequency wavelength. 8. Repeat steps 5 through 7 using a different frequency. Trial Number of Vibrations in 10 s Frequency (Hz) Wavelength (cm) Wave Speed (cm/s) Form a Hypothesis 9. Form a hypothesis about the relationship between frequency and wavelength. Test Your Hypothesis 10. Choose a frequency that you did not use during Make Observations. Predict the wavelength for a wave with this frequency. 11. Practice making a wave on the spring toy with your chosen frequency. Repeat steps 4 7 for this wave. Did your prediction of wavelength support your hypothesis? If not, revise your hypothesis and repeat steps 4 7. Lab Tips Keep the amplitude constant by moving the same distance on the y-axis in each vibration. Twenty vibrations in 10 s make a wave with a frequency of 2 Hz. Waves 67

74 Lab B continued Analyze and Conclude 12. Conclude How did your prediction of wavelength compare to your measurement? 13. Think Critically What measurements were the most difficult to make accurately? Suggest ways to improve on the method. 14. The Big Idea How did the wavelength, frequency, and wave speed change for the different waves that you created? Communicate Your Results Write a report explaining the steps you took in this lab. Include a table of the measurements you made. Be sure to describe sources of error in your measurements and ways that you might improve the accuracy of your experiment. Remember to use scientific methods. Make Observations Ask a Question Extension Form a Hypothesis Test your Hypothesis Analyze and Conclude Communicate Results Try measuring the wave speed of other waves. Try stretching your spring toy to different lengths or try measuring the wave speed of longitudinal waves. You also might try working with ropes of different thicknesses, different spring toys, or even water in a wave tank. 68 Waves

75 Lab C Water Waves Direction: Use the information and data from the Lab Measuring Wave Speed to perform this lab. You have learned that a wave carries energy and transfers energy from one place to another and that waves can travel at different speeds. There are many kinds of waves such as light waves, sound waves, and water waves. In this investigation, design an experiment to create water waves of different speeds. Please note that you must complete Lab B before beginning Lab C. Have your teacher approve your design and safety procedures before beginning your experiment. Waves 69

76 Chapter Key Concepts Builder Waves End-of-Chapter Practice Directions: Work with a group to create a display about waves. Here are the steps you must take to complete this activity: As a group, decide what you would like to demonstrate. First, make a list of what you could demonstrate. Then, write what the group decides would be best to demonstrate. Things we could demonstrate: What will be best to demonstrate: Why this will be best to demonstrate: Then, List the materials you will need: Present your demonstration to the class. List the different responsibilities of group members: Things to remember when you prepare your group s demonstration: All group members must participate in some way. The demonstration must be well organized. The demonstration must convey a main concept about waves. Be prepared to answer questions about waves from your classmates. List the steps the group must take to create the demonstration: 70 Waves

77 Chapter Test A Waves Multiple Choice Directions: On the line before each statement, write the letter of the correct answer. 1. Only electromagnetic waves can move through A. water. B. space. C. solid rock. 2. In a transverse wave, a measure of the distance from one trough to the next is the wave s A. frequency. B. amplitude. C. wavelength. 3. In a wave, particles move parallel to the direction in which the wave travels. A. transverse B. rarefaction C. longitudinal Completion Directions: On each line, write the term from the word bank that correctly completes each sentence. Each term is used only once. absorption reflection refraction speed transmission vibrates 4. The of a wave depends on the material it travels through. 5. is the transfer of energy by a wave to the medium through which it travels. 6. is the passage of light through an object. 7. The frequency of a wave indicates how fast the source of the wave. 8. During, waves bounce off a surface. 9. When a wave changes direction because of a change in speed, occurs. Waves 71

78 Chapter Test A continued Interpreting a Diagram Directions: Use the diagram to respond to each statement. Wave 1 Wave 2 a a d d c b c c b c 10. Identify the letter that points to the wave crests. Then identify the letter that points to the wave troughs. 11. State what is being measured by label C in the diagram. 12. Determine which wave carries more energy, Wave 1 or Wave 2. Short Answer Directions: Respond to each statement on the lines provided. 13. Describe the way a wave s frequency changes as its wavelength decreases. 14. A transverse wave is passing through a medium. Tell the direction in which the particles of the medium move when the wave itself moves horizontally. 15. Define wave. 72 Waves

79 Chapter Test A continued Concept Application Directions: Respond to each statement on the lines provided. Use complete sentences. 16. State the law of reflection in your own words. 17. Explain when wave interference occurs. 18. Describe how sound waves are affected by diffraction when they travel through an open doorway. Give an example of how this might be experienced by a listener standing outside a noisy room. Waves 73

80 Chapter Test B Waves Multiple Choice Directions: On the line before each question or statement, write the letter of the correct answer. 1. Only electromagnetic waves can move through A. air. B. soil. C. water. D. space. 2. The distance from one crest to the next is a wave s A. trough. B. frequency. C. amplitude. D. wavelength. 3. In which type of wave do the particles in a medium move parallel to the direction of the wave movement? A. transverse wave B. rarefaction wave C. longitudinal wave D. electromagnetic wave Completion Directions: On each line, write the term from the word bank that correctly completes each sentence. Not all terms are used. absorption amplitude reflection refraction speed transmission vibrates wavelength 4. The of a wave depends on the material it travels through. 5. is the transfer of energy by a wave to the medium through which it travels. 6. is the passage of light through an object. 7. The frequency of a wave indicates how fast the wave s source. 8. During, waves bounce off of a surface. 9. When a wave changes direction because of a change in speed, occurs. 74 Waves

81 Chapter Test B continued Interpreting a Diagram Directions: Use the diagram to answer each question or respond to each statement. Wave 1 Wave 2 a a d d c b c c b c 10. Identify the following parts of the wave in the diagram: A: B: 11. Determine what label C is measuring in the diagram. 12. State which wave carries more energy. Explain how you can tell. Short Answer Directions: Respond to each statement on the lines provided. 13. Explain the relationship between wavelength and frequency. 14. Describe the movement of particles in a medium as a transverse wave passes through. Waves 75

82 Chapter Test B continued 15. Defend or refute the following statement: Waves transfer energy but do not produce it. Concept Application Directions: Respond to each statement on the lines provided. Use complete sentences. 16. If light waves hit a surface at a 45 angle, determine the angle at which they will bounce off that surface. Explain why this is the case and include the scientific law that governs this interaction. 17. Contrast constructive and destructive interference. 18. Apply what you know about diffraction to differentiate how sound waves and light waves react differently inside a building. Use this information to explain why you can often hear someone in a building before you can see the person. 76 Waves

83 Chapter Test C Waves Multiple Choice Directions: On the line before each question, write the letter of the correct answer. 1. The Sun s energy can move through space because it travels as A. seismic waves. B. mechanical waves. C. compression waves. D. electromagnetic waves. 2. The wavelength of a wave is the distance A. it travels in one second. B. it travels from its source. C. from one crest to the next crest. D. from one crest to the next trough. 3. A longitudinal wave makes particles in a medium A. move in a circle. B. move at right angles to wave movement. C. move back and forth parallel to wave movement. D. move in the opposite direction of wave movement. Completion Directions: On each line, write the term that correctly completes each sentence. 4. The of a wave depends on the material it travels through. 5. is the transfer of energy by a wave to the medium through which it travels. 6. is the passage of light through an object. 7. The frequency of a wave indicates how fast the source of the wave. 8. During, waves bounce off a surface. 9. When a wave changes direction because of a change in speed, occurs. Waves 77

84 Chapter Test C continued Interpreting a Diagram Directions: Use the diagram to answer each question or respond to each statement. Wave 1 Wave 2 a a d d c b c c b c 10. Identify the following parts of the wave in the diagram: A: B: C: 11. Identify what the dotted line represents in both diagrams. How is it used to measure waves? 12. Compare and contrast the two waves shown. What can you tell about these waves and the amount of energy they carry? Short Answer Directions: Respond to each statement on the lines provided. 13. A set of waves has a frequncy of 0.5 Hz. Four hours later, the waves have a frequency of 2 Hz. Determine what has happened to their wavelength. 78 Waves