TEACHER’S GUIDE
TEACHER’S GUIDE
Students are usually eager to share the answers they got to the
questions they raised before the show.After reviewing the new information that they learned, ask what else they would like to know about
this topic…
www.aip.org/physnews/preview/1996/chain/link3.htm
This page from the American Institute of Physics describes the interesting
phenomenon of transforming sound energy into light energy.
Raising a thought-provoking question would be a good way to assess
the overall depth of understanding. A suggestion is listed below:
• Discuss the fact that some sounds not heard by the human ear
can be heard by other animals and identified by technical instruments.
• Discuss why sound energy does not travel in outer space.
• Have students discuss the answer to the question about the tree
falling in the forest.
TEACHER’S GUIDE
Suggested Print Resources
• Grimshaw, Caroline. Sound. World Book, Inc., New York, NY; 1999.
• Lampton, Christopher. Sound: More Than What You Hear. Enslow,
Springfield, NJ; 1992.
• Wood, Robert. Sound Fundamentals. McGraw Hill, New York, NY;
1997.
Sound
Follow-up Activities
• Replicate the “mystery of the soundless bell” investigation.
• Integrate information learned in this show with a music class by
asking your school’s music teacher to demonstrate pitch and identify
some instruments that produce sounds of different frequencies.
Using a set of tuning forks, have students investigate
different pitches, and have them experiment with different media, to
see which ones insulate sound waves and which ones transmit
sound waves/vibrations.
• Have each student choose a specific modern application of sound
energy (sonar, ultrasound , music…) to research and report on.
• Discuss the many facets of sound energy and create a bulletin board
describing sound and defining terms often used when talking about
sound.Terms to include: wavelength, frequency, amplitude, interference, resonance, harmony.
Internet Resources
Periodically, Internet Resources are updated on our Web site at
www.libraryvideo.com
www.fi.edu/fellows/fellow2/apr99/soundindex.html
The Franklin Institute helped develop this excellent fifth-grade site
explaining sounds and how we hear them, and offers examples of
sound experiments to try.
Grades 5–8
S
TEACHER’S GUIDE CONSULTANT
Conrad M. Follmer
25 years as a K–5 Science & Math Coordinator for a Pennsylvania public
school system, currently an independent consultant to elementary schools.
TITLES
• ATOMS & MOLECULES
• CHANGES IN PROPERTIES
OF MATTER
• CHARACTERISTICS OF WAVES
• ELECTRICITY
• ELEMENTS, COMPOUNDS
& MIXTURES
• FLIGHT
• FORCES
Teacher’s Guides Included
and Available Online at:
library.thinkquest.org/19537/
The Soundry is a Think Quest Web site designed by students to
explain the physics of sound. It includes an interactive Sound Lab as
well as clear explanations of many modern applications of sound.
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3/04
• FRICTION
• GRAVITY
• LIGHT
• MAGNETISM
• MOTION & BALANCE
• THE PERIODIC TABLE
• PROPERTIES OF MATTER
• SIMPLE MACHINES
• SOUND
After Viewing: Have your students share video excerpts
that fascinated or surprised them, then challenge your students to prove or disprove the accuracy of the facts they
put on their “Everything We Think We Know About…” list.
Discuss what else they learned and use the follow-up questions and activities to inspire further discussion. Encourage
students to research the topic further with the Internet and
reading resources provided.
800-843-3620
Teacher’s Guide and Program Copyright 2000 by Schlessinger Media,
a division of Library Video Company
P.O. Box 580, Wynnewood, PA 19096 • 800-843-3620
Executive Producers: Andrew Schlessinger & Tracy Mitchell
Programs produced and directed by First Light Pictures, Inc.
All rights reserved
tudents in grade 5–8 classrooms possess a wide range of
background knowledge. Student response to this video
program is sure to be varied, so the teachers at these grades
need all the help they can get! This guide has been designed
to help the 5–8 science teacher by providing a brief synopsis of the program, previewing and follow-up questions,
activities, vocabulary and additional resources.
Before Viewing: Extensive research tells how important
it is for the teacher to discover what the students know —
or think they know — about a topic, before actually starting a new unit.Therefore, after prompting discussion with
the pre-viewing questions, lead your class to create a
“Everything We Think We Know About…” list.You may also
wish to preview key vocabulary words, and have students
raise additional questions they hope will be answered.
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Program Summary
Sound is energy that travels through a medium in waves.When an object
moves back and forth, or vibrates, the molecules around the object also
vibrate. Each molecule moves back and forth only a tiny distance, but it is
enough to create areas where there are many molecules pushed close
together, called compressions, and areas where molecules are spread far
apart, called rarefactions.A compression is also called a wave crest, while
a rarefaction is called a wave trough.
Scientists measure sound waves in a number of ways. Amplitude is a
measure of how loud a sound wave is and is measured in units called
decibels (dB). Sounds that are louder than 120 decibels, like jet engines
and rock concerts, are at a dangerous level for the human eardrum.
Frequency is the number of waves that pass a given point each second
and determines the pitch of a sound. As the frequency, or the number
of vibrations increases, the pitch of a sound becomes higher. A low
frequency sound is a rumble and a high frequency sound is a whistle.
Sound wave frequencies are measured in units called hertz, or waves per
second. Humans can hear sounds from 20 hertz to 20,000 hertz, while
dogs can hear sounds up to 35,000 hertz. Dolphins can hear all the way
up to 150,000 hertz! Humans can hear because of the vibration of the
eardrum and bones in the inner ear. These vibrations are sent to the brain
as nerve impulses where they are interpreted, identified and heard as specific sounds.
Sound needs a medium like air, water or stone in order to travel. The
reason that outer space is so quiet, even though incredible explosions are
constantly happening on the sun and on every other star, is that space is a
vacuum.A vacuum has no atoms to vibrate; therefore, outer space is silent.
No medium, no sound! An investigation confirms that a medium is necessary for sound energy to be transmitted. Sound travels at different speeds
through different mediums.The denser the medium, the faster sound can
travel through it. Sound travels almost five times faster in water than air
and 20 times faster in solids like rock.The average speed of sound is 340
meters per second; anything faster is described as supersonic.
Vocabulary
The following words are included for teacher reference or for use with
students. They are listed in the order in which they appear in the video.
sound — Energy that travels from a moving (vibrating) object through
the particles of a medium.Without vibrations, there would be no sound.
medium — The material through which a wave travels. Light waves do
not need a medium and therefore can travel through the vacuum of
space. Sound waves must have a medium in order to travel.
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longitudinal wave — The type of wave made by sound. In longitudinal
waves, the particles of the medium vibrate in the direction of the moving
energy.
compressions — As a sound wave travels, it squeezes then releases the
particles.The squeezing is a compression, crest.
rarefactions — As a sound wave travels, it squeezes then releases the
particles.The releasing is a rarefacion, trough.
crest — The high point of a wave.
trough — The low point of a wave.
amplitude — The height of a sound wave. A measure of how loud a
sound wave is.
decibel (dB) — The unit of measurement of loudness. Sounds louder
than 120 decibels are harmful to the human ear.
wave — A disturbance (vibration) that moves energy through a medium
or space.A wave cannot exist only in one place, but must extend from
one place to another.
wavelength — Measurement of the distance between two consecutive
high or two low points on a wave.
frequency — Measurement of the number of waves that pass an established point in a given amount of time.Waves with higher frequency have
more energy than waves with lower frequency.
pitch — The position of a sound within the complete range of sounds.As
the frequency, or number of vibrations, increases, the pitch of a sound
becomes higher.The lower the frequency, the lower the pitch. A shrill
whistle has a high pitch.
hertz — A unit of frequency equal to one cycle per second.
echolocation — Using sound waves to locate distant things.
sonar — Sound Navigation And Ranging.A high-tech form of echolocation used by ships.
Mach one — The average speed of sound, about 1,230 kilometers per
hour.
supersonic — Faster than the speed of sound.
density — The amount of matter in a given space. A measure of how
compact particles are in a medium.
elasticity — The quality describing how quickly the particles of a
medium bounce into one another.
• Can sound travel through water? Concrete?
After the class has completed their “Everything We Think We Know
About…” list, ask them what other questions they have that they hope
will be answered during this program. Have students listen closely to
learn if everything on their class list is accurate and to hear if any of
their own questions are answered.
Focus Questions
1.
2.
3.
4.
5.
6.
7.
How is sound defined?
How do sound waves travel?
Is outer space silent? Why?
What are the components of a sound wave?
Why do we say that sound travels in longitudinal waves?
What is the difference between compression and rarefaction?
How do the terms ‘crest’ and ‘trough’ relate to compression and rarefaction?
8. What is amplitude? How is it measured?
9. Why are sounds with high decibel levels dangerous?
10. What is wavelength?
11. How are the pitch and frequency of a sound related? Give
examples of sounds with high or low pitch.
12. How is sound frequency measured?
13. What is a hertz?
14. How does the human ear hear sounds?
15. Dolphins and bats use echolocation.What is it?
16. What is sonar?
17. What was learned from the “soundless bell” investigation?
18. What does it mean if a jet can fly at supersonic speed?
19. What does the density of a medium have to do with the speed of
sound?
20. Can you explain why sound travels faster in stone and water than
in air?
Follow-up Discussion
Before students generate their list of “Everything We Think We Know
About…” for this topic, stimulate and focus their thinking by raising these
questions so that their list will better reflect the key ideas in this show:
• What is sound?
• How fast does sound travel?
Because research indicates that students will retain their previous
misconceptions, in preference to the new information, until they
actively recognize and correct their own errors, it is important to have
your students examine the facts/beliefs they put on their “Everything
We Think We Know About…” list. You may wish to have your class go
through the list, marking each entry with a “+” or an “-,” to show which
were correct and which were incorrect.
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Pre-viewing Discussion
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