READING THE WAVES
Grades 4 - 6

From the time we are developing as unborn babies to the day we die, sounds are all around us. You know sound can be a loud bang or a symphony orchestra. Yet, have you ever taken time to observe what sounds are made of? The video segments used in this lesson will reveal the parts of sound and what factors control sound. The viewing and post-viewing activities serve to reinforce the video segments using worksheets and hands-out experiments. The lesson is divided into five one-hour segments.

Minds on Science - "Sound All Around"

Students will be able to:

• explain what a sound wave is and draw one;
• list sounds in their school area and explain what they are made of;
• define the Doppler Effect;
• explain how sound reacts in: air, the absence of air, water;
• explain what makes sound: higher or lower, louder or softer.

Per group of 3 or 4:

• previously used office paper that has one clean side
• pencil
• rubber band
• Pyrex glass flask
• water
• stopper for flask
• cup hook
• string (6 in)
• tiny bell
• paper cup
• scissors
• balloon
• ticking wrist watch

Per Student:

• handouts, provided at end of this lesson (FOCUS FOR VIEWING worksheets for Lessons 1-5, and a Sound Wave Chart)
• pencil or pen
• notebook

Per Class:

• chart paper and marker
• heat source
• large bell, or cymbal
• mallet
• binoculars
• stop watch, or wrist-watch with sweep second-hand
• pencil/paper
• alarm clock
• 10-foot cord

• sound waves
• vocal cords
• Doppler Effect
• frequency
• bell jar
• air
• light waves
• vacuum
• transmit
• amplitude

In groups of 3 or 4, have the students list all the sounds they hear in the classroom. Next, go outside and have them continue their list by writing down the sounds they hear around the school grounds. Once they are back in the classroom, make a chart comprised of the group lists and discuss the sounds on the chart.

Discuss what made each sound. Hand out the Sound Wave Chart (attached) and discuss the parts of a sound wave. Finally, discuss and define the vocabulary list.

First Segment

To give a specific focus for viewing, students should be directed to list what sound sources are presented, and what devices were used to recreate and record sounds.

Second Segment

On another day, explain that this next video segment presents Kim's voice, vocal cords, the bel jar and the concept of a vacuum. To provide a specific focus for viewing, direct students to look for what transmits sound and what a sound wave is.

Third Segment

On another day, explain that this segment presents the video recording of different sounds. To give students a specific focus for viewing, direct them to list the sounds that will be recorded. They are then to state the factors that make sounds higher/lower and softer/louder. List differences between light and sounds waves. Distribute FOCUS FOR VIEWING Worksheet #3.

Fourth Segment

On another day, explain that the next segment presents the Doppler Effect. To give students a specific focus for viewing, distribute Focus For Viewing Worksheet #4, and tell them to jot down a definition of the Doppler Effect as they view the video segment.

Fifth Segment

The final segment explains how certain sound waves can be felt. Students should be able to explain why loud sounds can hurt you. To give students a specific focus for viewing, have them turn their attention to how physicians use sound waves to diagnose and cure medical problems. Distribute Focus for Viewing Worksheet #5.

First Segment
START tape. PLAY through the entire program (approximately 15 minutes). Discuss Kim's problem (REWIND the tape to the part showing a video of vocal cords). Answer the questions for Focus for Viewing #1.

Second Segment

START at the segment of the program that shows a video of vocal cords in action.
PLAY through until you reach the end of the explanation of what a sound wave is.
STOP. Have the students answer the questions on the work-sheet section headed FOCUS FOR VIEWING, Worksheet #2.

Third Segment

RESUME PLAY through to the start of the explanation of the Doppler Effect.
STOP. Students should answer the questions on the worksheet section headed Focus for Viewing #3.

Fourth Segment

PLAY through the entire explanation of the Doppler effect.
Students should answer the questions on the worksheet headed Focus for
Viewing #4.

Fifth Segment

RESUME PLAY through his segment until the end of the program.
Instruct students the answer the questions in the worksheet section headed Focus for Viewing #5.

First Segment

This experiment will show that sound waves are vibrations.
Working in groups of 3 or 4, students will hold the ends of a rubber band by the thumb and index finger of each hand and stretch the rubber band. Pluck the rubber band and observe the vibrations. Stretch the rubber bands some more and pluck again. Note the change of the vibrations and the change of the sound's pitch. Ask each student to record notes about this experiment in their notebooks.

Second Segment

This experiment approximates the demonstration on using the Bell Jar that was viewed. (If your school has a bell jar, by all means, use it.)
Tie a tiny bell to a string and tie the other end of the string to a cup hook. Attach the cup hook to a cork or rubber stopper. Place an inch of water in a Pyrex glass flask and heat the water to a boil. Remove the flask from the heat source. About ten seconds later place the stopper into the flask and allow it to cool. Shake the flask. Can you hear the bell? Compare by loosening the stopper so air can enter the flask. Replace the stopper and shake again. Does the bell sound louder at this time? Record the results of this experiment.

The next experiment proves that sound travels through water.
It also proves that sound travels through water more easily than it does through air.
Fill a balloon with water. Place your ear against the balloon and listen tot he ticking of a watch by resting the watch on the opposite side of the balloon. Remove the balloon and listen to the watch. Which is louder? Discuss and record the experiment in student notebooks.

Third Segment

This experiment will show that light waves travel faster than sound waves.
Divide the class into two groups. Place the groups 200 yards apart. Give one group a large bell and a mallet. Give the other group a stop watch, pencil and paper. Ring the bell. The recording group is to start the watch as they observe the bell being struck (view through the binoculars) and stop the watch when they hear the sound of the bell. Knowing the distance and time, you can calculate the speed of sound.

Fourth Segment

This experiment is designed to demonstrate the Doppler Effect.
Tie an alarm clock on a ten-foot cord. Start the alarm clock ringing. Whirl the clock around your head. The pitch of the sound will get lower as the clock flies away from you and higher as it gets toward you. This is because the sound waves come from the clock faster as the clock moves toward the listener and are stretched as the clock moves away in the backward phase of the swing.

Fifth Segment

This experiment makes a crude stethoscope.
In groups of 3 or 4, students will cut out the bottom of a paper cup. Hold the hole tot he ear and place the end on someone's chest. The person's heartbeat will be heard. Next, hold an ear to the students chest without the aid of the cup. They will hear the heartbeat but not as loud. This happens because the cup isolates and concentrates the air column that transmits the sound of the heartbeat to your ear.

• Take a field trip to a hospital and have the sound equipment demonstrated.
  
  
• Make an audit of the harmful sounds in school and at home. Come up with suggestions on how to either reduce the sounds or how to protect yourself from their harmful effects. Publish an article on harmful noise in the school newsletter.

SOCIAL STUDIES:
Make study o the recording industry and have kids explore how sound is reproduced in the recording industry. If your school is near a recording facility (or even a radio studio which produces local studio programming), arrange a field trip.

MATH:
Introduce plane geometry and sound waves, and translate the parabola of the wave into a mathematical equation.

ARCHITECTURE/DESIGN:
Explore how buildings are built and how acoustical problems are overcome.

MOTION PICTURE SPECIAL EFFECTS:
Find our how sound special effects are produced.

Master Teacher: Craig Russell
Mountain Lake Public Broadcasting/Plattsburgh, NY