Lesson Plan in Science
I. Objectives
At the end of the lesson, the students will be able to:
1. describe the characteristics of sound;
2. identify how organisms produce, transmit, and receive sound of various frequencies
(infrasonic, audible, and ultrasonic sound)
II. Subject Matter
A. Topic: Sound
B. Materials: Visual aids, pictures, handkerchief, cotton balls
C. References:
 Science Learner’s Material (Quarters 1-4) 7, pp. 31-34
 Exploring Life Through Science Series, The New Grade 7, pp. 225-231
D. Science Process: Observing, Communicating, Comparing, Classifying
E. Value Integration: To appreciate the importance of sound
III. Learning Task
Teacher’s Activity
A. Preliminary Activities
1. Prayer & Greetings
2. Checking of Attendance
3. Review/Motivation
Ask the students about the previous discussion.
Student’s Activity
Our previous lesson was about waves.
B. Lesson Proper
1. Unlocking of difficult terms
 vacuum – an empty space in which there is
no air or other gas
 larynx – part of the throat that contains the
vocal cords
 frequency – the number of occurrences of a
repeating event per unit of time
 audible – loud enough to be heard
2. Activity
”How Good Is Your Hearing?”
Procedure
1. Blindfold a volunteer.
2. Some of the students will stand forming a
circle around the volunteer.
3. The students will take turn making gentle
noises, such as a clap, a click of the fingers, a
whisper or a quiet call.
4. After each sound, the person with the
blindfold should point to where they think the
sound is coming from.
5. Try it again and this time with a cotton ball
on the ears of the blindfolded volunteer.
3. Analysis
What is sound?
Sound is a form of energy that travels
in invisible waves created by vibrating
objects. It cannot travel in vacuum.
Production of Sound
The source of sound is any vibrating object. The
vibration of the vocal chords in the larynx
produces human voice and also animals.
The Audible Range
The audible range of frequency for humans is
from 20 – 20 000 Hz.
What is infrasound?
Sounds whose frequencies are lower
than 20 Hz.
Sources of infrasonic
Natural events: avalanches, earthquakes,
volcanoes, waterfalls, calving of icebergs,
meteors, and lightning
Animal communication: whales, elephants,
hippopotamuses, rhinoceros, giraffes, alligators
What is ultrasound?
Sounds with frequencies higher than
20 000 Hz.
They are used by some animals like bats
(echolocation), insects, dogs, cats, and dolphins.
Imaging is the most common use of ultrasound
in medicine.
Characteristics of Sound
What is pitch?
Pitch refers to the highness and
lowness of a sound.
According to the basic wave equation, a highfrequency sound gives rise to a short wave and
a low-frequency sound, to a long wave.
What is loudness?
Loudness refers to the loudness and
softness of a sound.
Sound Levels of different sound sources
Source of sound
Level (dB)
Jet engine, 30 m away
140
Threshold of pain
120
Amplified rock music
115
Old subway train
100
Average factory
90
Busy street traffic
70
Normal conversation
60
Library
40
Close whisper
20
Normal breathing
10
Threshold of hearing
0
What is quality or timbre?
It is perceived as the quality of
different sounds.
The Human Voice
The human voice is regarded as the most
wonderful musical instrument. The vibration of
the vocal cords in the larynx produces music.
What is noise?
4. Abstraction
What is sound?
How does sound produced?
What are the characteristics of sound?
5. Application
What would the world be if there is no sound?
Noise is a term used to refer to an
unwanted or damaging sound.
Sound is a form of energy that travels
in invisible waves created by vibrating
objects.
Sound is produced by any vibrating
objects.
Pitch, loudness, and quality.
The world will be quiet and peaceful.
IV. Evaluation
Identification
1. A longitudinal wave that is created by vibrating objects
2. Sounds whose frequencies are lower than 20 Hz
3. Sounds with frequencies higher than 20 000 Hz
4. Threshold of pain (dB)
5. Refers to the highness and lowness of a sound
6. What is Hz?
7. What is dB?
8. Refers to the loudness and softness of a sound
9. The most wonderful musical instrument
10. Unwanted or damaging sound
V. Assignment
Bring any material that produces sound.
M.L.: ___________
I.D: ____________
Prepared by:
Patricia Ann F. Palencia
BSED IV – Bio.Sci.