WHAT AM I?WHAT AM I?

Is there a Is there a relationship between relationship between

the amplitude of sound the amplitude of sound and the loudness of and the loudness of

sound? sound?

Loudness and Loudness and amplitude of sound is amplitude of sound is

directly proportional to directly proportional to each other. The greater each other. The greater

the amplitude of the the amplitude of the sound wave that sound wave that

reaches your eardrum, reaches your eardrum, the greater the the greater the

perceived loudness of perceived loudness of the sound.the sound.

What characteristic What characteristic of sound helps us to of sound helps us to identify sources of identify sources of

sound?sound?

Timbre or tone Timbre or tone quality of a sound is used quality of a sound is used

to distinguish between to distinguish between two different sounds. two different sounds.

This tone quality is very This tone quality is very important since it helps important since it helps

us to identify what us to identify what produced the sound.produced the sound.

What are the different What are the different factors affecting the factors affecting the

pitch of a sound?pitch of a sound?

Factors affecting the pitch of a sound:1.1. Lengthening of the stringLengthening of the string

– The shorter the length of the string, The shorter the length of the string, the higher the magnitude of the pitch.the higher the magnitude of the pitch.

2.2. Thickness of stringThickness of string– As the diameter of a string decreases As the diameter of a string decreases

the pitch of the sound wave increasesthe pitch of the sound wave increases3.3. Tautness of stringTautness of string

– The tighter the string is, the greater The tighter the string is, the greater of pitch of sound is produced.of pitch of sound is produced.

4.4. Length of air column Length of air column - the shorter the air column the greater - the shorter the air column the greater the pitch of sound.the pitch of sound.

How is frequency How is frequency and pitch related?and pitch related?

The greater the The greater the frequency of sound frequency of sound

wave, the higher the wave, the higher the pitch of sound wave pitch of sound wave

produced.produced.

What are the What are the characteristics of characteristics of

sound?sound?

Characteristics of sound Characteristics of sound wave:wave:

1.1. LoudnessLoudness• Loudness of sound Loudness of sound

largely depends on the largely depends on the intensity of sound.intensity of sound.

• The greater the The greater the amplitude, the louder amplitude, the louder the sound producedthe sound produced

2. Intensity2. Intensity• The measure of the The measure of the

energy per unit time energy per unit time transmitted through a transmitted through a unit area by the sound unit area by the sound wave.wave.

• Intensity levels are Intensity levels are expressed in decibels expressed in decibels (dB)(dB)

2. Pitch and frequency.2. Pitch and frequency.•Pitch refers to the highness Pitch refers to the highness or lowness of soundor lowness of sound

•The pitch sound depends on The pitch sound depends on the frequencythe frequency

•The greater the frequency, The greater the frequency, the higher the pitch of soundthe higher the pitch of sound

3. Timbre or tone quality.3. Timbre or tone quality.•Timbre or tone quality of a Timbre or tone quality of a sound is used to distinguish sound is used to distinguish between two different sounds.between two different sounds.

•Tone quality is very important Tone quality is very important since it helps us to identify since it helps us to identify what produced the sound.what produced the sound.

ValuingValuing

Sound can be pleasant or unpleasant. Sound can be pleasant or unpleasant. Noise is categorized as an unpleasant Noise is categorized as an unpleasant

sound. Most countries are now affected sound. Most countries are now affected not only by air pollution . Both are not only by air pollution . Both are

harmful to one’s health. For instance, harmful to one’s health. For instance, noise caused by the honking of horns, noise caused by the honking of horns,

shrilling voices and scuffling of feet can shrilling voices and scuffling of feet can aggravate a sick person’s condition. aggravate a sick person’s condition. Scientists have found out that people Scientists have found out that people get more work done in quiet places get more work done in quiet places than in noisy areas. In fact, a person than in noisy areas. In fact, a person

can do 25% more work in a quiet room. can do 25% more work in a quiet room. Knowing all these:Knowing all these:

1.1. How would you behave in the How would you behave in the school campus during your school campus during your

vacant periods?vacant periods?

2.2. How would you walk along the How would you walk along the corridors?corridors?

3.3. What must be your behavior in What must be your behavior in the library? In the canteen? the library? In the canteen?

Why?Why?

4.4. Why are “Quiet” signs placed in Why are “Quiet” signs placed in hospitals?hospitals?

AssessmentAssessment

1)1) How can the pitch of a How can the pitch of a vibrating string be made vibrating string be made

higher?higher?a.a. Tighten the stringTighten the stringb.b. Change to a thick string of Change to a thick string of

a same kinda same kindc.c. Reduce its lengthReduce its length

A)A) a onlya only C) a and c only C) a and c onlyB)B) b onlyb only D) b and c only D) b and c only

2)2) The same note The same note mimi is played on is played on a piano and on a violin. Which a piano and on a violin. Which

characteristic distinguishes characteristic distinguishes the sound coming from the the sound coming from the

two instruments ?two instruments ?

A)A) PitchPitchB)B) LoudnessLoudnessC)C) QualityQualityD)D) IntensityIntensity

3)3) Increasing the amplitude of a Increasing the amplitude of a sound wave increases itssound wave increases its

A)A) PitchPitchB)B) LoudnessLoudnessC)C) QualityQualityD)D) IntensityIntensity

4) Increasing the frequency of a 4) Increasing the frequency of a sound increases its sound increases its

A)A) PitchPitchB)B) LoudnessLoudnessC)C) QualityQualityD)D) IntensityIntensity

5) What happens to the pitch of 5) What happens to the pitch of sound wave when you decrease sound wave when you decrease

the length of air column? the length of air column?

A)A) DecreasesDecreasesB)B) IncreasesIncreasesC)C) Remains the sameRemains the sameD)D) None of the aboveNone of the above

1.1. CC2.2. CC3.3. DD4.4. AA5.5. BB

Answer KeyAnswer Key

ASSIGNMENTASSIGNMENT

Describe how different Describe how different sound is produced by sound is produced by musical instruments. musical instruments.

(pp. 375 S&T IV)(pp. 375 S&T IV)