8.6.1-3-Sound

Chapter 6
Sound

Lesson 6.1
Producing and Detecting Sound

Essential Questions:

1. How is a sound produced?

2. How does sound move from one place to another?

3. Why does sound travel at different speeds through various materials?

4. What are the functions of the different parts of the human ear?

What is Sound?

Sound is a form of energy that behaves in a predictable way.

What Causes Sound?

Sound is made because of vibrations.

What are Vibrations?

Vibrations are back-and-forth motions....WAVES.

Waves

In physics, a wave travels through matter transferring energy from one place to another.

Two Types of Waves

Mechanical v. Electromagnetic

Mechanical Waves

• These need to travel through a medium (liquid, gas, or solid). *They CANNOT move through a vacuum.

• Sound is a mechanical wave.

Electromagnetic Waves

• These DO NOT need to travel through a medium (liquid, gas, or solid). *They CAN move through a vacuum.

• Examples of electromagnetic waves include light, microwaves, radio waves, and X-rays.

Multiple Choice

A wave is a disturbance that transfers _____ from one place to another.

• Water

• Air

• Matter

• Energy

• Electrons

Multiple Choice

What kind of waves vibrate our eardrums so we can hear?

• Microwaves

• Water Waves

• Light Waves

• Sound Waves

• Radio Waves

Multiple Choice

What kind of waves require some sort of medium to travel through?

• Mechanical waves

• Electromagnetic waves

• All of the above

• None of the above

Multiple Choice

What kind of waves can travel through a vacuum?

• Mechanical waves

• Electromagnetic waves

• All of the above

• None of the above

Multiple Choice

What kind of waves transfer energy?

• Mechanical waves

• Electromagnetic waves

• All of the above

• None of the above

Multiple Choice

Sound is an example of what type of wave?

• Mechanical waves

• Electromagnetic waves

• All of the above

• None of the above

Multiple Choice

A wave is a disturbance that transfers _____ from one place to another.

• Water

• Air

• Matter

• Energy

• Electrons

Multiple Choice

What kind of waves vibrate our eardrums so we can hear?

• Microwaves

• Water Waves

• Light Waves

• Sound Waves

• Radio Waves

Multiple Choice

What kind of waves require some sort of medium to travel through?

• Mechanical waves

• Electromagnetic waves

• All of the above

• None of the above

Multiple Choice

What kind of waves can travel through a vacuum?

• Mechanical waves

• Electromagnetic waves

• All of the above

• None of the above

Multiple Choice

What kind of waves transfer energy?

• Mechanical waves

• Electromagnetic waves

• All of the above

• None of the above

Multiple Choice

How does sound travel?

• by vibration

• by air

• it starts with the mechanical movement of the molecules

• by the space

Multiple Choice

What is vacuum?

• is the space

• is a chamber with molecules and particles

• is a space where there is no molecules,no matter , no vibration

• is a space where there is no sound

Sound Waves

• Molecules move by pushing forward and spreading

• Needs matter to travel through

Sound Waves

• Transmitted (passes) through matter (thats why you can hear music from another room)

• Reflected - Waves hitting matter and bouncing off (this is why you hear echoes)

• Absorbed - Transfer of energy of wave with medium it comes into contact with. (no echo)

Multiple Select

What are the different properties of waves?

• Amplitude

• Frequency

• Swells

• Wavelength

Sound Energy

Energy that travels in waves, but unlike electromagnetic energy, it cannot travel
through empty space.

What is sound?

• Sound is a form of energy.

• Sound travels in waves.

Sound occurs when..

• there is a back-and-forth movement called VIBRATION.

• You can see drums vibrate when you strike them or the strings on a guitar vibrate when you pluck them.

When strings are plucked on a guitar, the strings VIBRATE to create sound energy!

BIG vibrations...

• make LOUD sounds!

Small vibrations...

• make quiet sounds

Sound must have MATTER to travel through.

• Think of the sound moving through the guitar string, or think of the rumble in your chest from a marching band during a parade.

• Thanks to air particles sound can travel freely on earth.

• Do you think there is sound in space?

  
  

Sound Energy

• sound is energy in the form of vibrations passing through matter

• A vibration is a quick back and forth movement.

• Sound occurs when objects vibrate.

• Sound travels through solids, liquids and gases.

• Sound cannot travel through empty space where there is no matter.

Multiple Choice

What is energy in the form of vibrations passing through matter?

• sight

• sound

• vibrations

Multiple Choice

What is a vibration?

• particles

• a quick back and forth movement

• a compression

Multiple Choice

Sound cannot travel through...

• solid

• liquid

• gas

• empty space

Multiple Choice

2. When vibration stops, the sound stops.

• TRUE

• FALSE

Sound Waves

• Molecules move by pushing forward and spreading

• Needs matter to travel through

Volume

• When we describe a sound, we often mention its loudness, or volume.

• Some sounds are louder than others.

• Volume is the measure of how strong or intense a sound seems to us.

• The more energy there is in the sound wave, the louder the sound.

Amplitude

• Height of wave from its resting point.

• The higher the amplitude of a wave, the more energy it has, and the louder it sounds.

Frequency

• How many waves pass a point in one second.

• Measured in hertz

Amplitude

Amplitude is also referred to as the wave height. The taller the wave, the louder the sound.

The higher amplitude the more energy!

Wavelength vocabulary

Amplitude examples

• A higher wave during a tsunami causes greater destruction.

• A louder sound wave can cause hearing damage.

Amplitude examples

• A higher wave during a tsunami causes greater destruction.

• A louder sound wave can cause hearing damage.

Multiple Choice

What is the measure of how strong or intense a sound seems?

• frequency

• volume

• pitch

Multiple Choice

What role does energy play in sound?

• Sound waves have nothing to do with energy.

• Sounds waves carry energy.

• Energy is present in loud sounds only.

• Energy is present in high-pitched sounds but not in low-pitched sounds.

Multiple Choice

What does volume measure?

• the speed of a sound

• the frequency of a sound

• the highness or lowness of a sound

• the loudness or softness of a sound

Multiple Choice

What does amplitude measure?

• frequency

• volume

• pitch

• echoes

Multiple Choice

What carries sound?

• particles in the air

• water

• ears

Multiple Choice

What do we call the path of vibrating particles through the air?

• air

• wave

• music

Multiple Choice

Which wave has a greater amplitude?

• Solid Line

• Dotted Line

Multiple Choice

Which wave has the quietest volume?

• 1

• 2

• 3

Multiple Select

Which two waves have the same amplitude? Choose 2 answers.

• 1

• 2

• 3

Multiple Choice

Which graph has the higher amplitude?

• Graph A

• Graph B

Multiple Choice

Isaiah has built a giant speaker so that he can play music really loudly. He has set the speaker right outside his neighbor’s house. What will happen to the glass window of the house when Isaiah starts playing music using the large speaker.

• The neighborhood dogs will start barking.

• The air around the speaker will heat up.

• The sound waves from the speaker will vibrate, causing the air near the speaker to vibrate. This will cause the window to move and possibly break.

• The speaker will use so much energy that the power will go out on the entire street.

“

SOUND WAVES - compressional waves formed
from vibrating objects colliding with air molecules

▹ Remember compressional waves are made of compressions

and rarefactions.

Labelling

Label the wavelength, compression and rarefaction of the longitudinal wave.

Drag labels to their correct position on the image

compression

rarefaction

wavelength

5

Speed of Sound -
depends on temperature
and state of medium

▹ Sound travels in solids and

liquids - molecules are closer
together than gas molecules

▹As a medium temp rises,
molecules move faster
conducting sound waves faster.

HUMAN
HEARING

STAGE 2

The middle of the
ear has three bones
called the hammer,

anvil and stirrup

which amplify sound

waves

STAGE 1
Ear gathers

compressional
waves which

vibrate a tough
membrane called

the eardrum

STAGE 3
The inner ear

contains the cochlea

which vibrates

sending auditory
nerve impulses to

the brain

STAGE 4

The brain decodes
and interprets nerve

impulses

INTENSITY

The amount of energy that
flows through a certain
area in a given amount of
time.

LOUDNESS

The human perception of

sound intensity which is

measured in decibels

Open Ended

Is loudness the same for every individual? Why or why not?

PITCH - how high or low a sound seems to be, which is

related to frequency of a sound wave

SUBSONIC

< 20 Hz

HUMANS CAN HEAR

20 - 20,000 Hz

ULTRASONIC

> 20,000 Hz

Lesson 6.2
Properties of Sound Waves

Essential Questions:

1. How are amplitude and intensity related to energy?

2. What is the relationship between frequency, pitch, and wavelength?

3. How can you recognize sounds from different sources?

4. In what ways are musical sounds produced?

Properties of Sound Waves

• Speed: Sound is fastest in solids, slower in liquids, and slowest in gases. It depends on the density and elasticity of the medium.
• Intensity and Loudness: Intensity is the rate at which a wave's energy flows through a given area. It depends on the wave's amplitude and distance from the sound source.

Multiple Choice

What factor determines the speed of sound in a medium?

• Density

• Elasticity

• Temperature

• Color

Elasticity

Did you know? The speed of sound in a medium is determined by its elasticity. Elasticity refers to the ability of a material to return to its original shape after being deformed. In general, materials with higher elasticity have faster speeds of sound. For example, sound travels faster in solids than in liquids or gases due to their higher elasticity.

The Science of Sound

• Intensity: Sound intensity levels are measured in decibels (dB). A 20 dB sound has 100 times more energy per second than a 0 dB sound.
• Loudness: It is a physical response to the intensity of sound and depends on factors like ear health and brain interpretation.
• Frequency and Pitch: Frequency is the number of wave cycles at a given time. Pitch is the perceived frequency of sound.

Multiple Choice

What is the unit of measurement for sound intensity levels?

• Watts

• Decibels

• Hertz

• Volts

Sound Intensity Levels

Trivia: The unit of measurement for sound intensity levels is decibels. Decibels are used to measure the loudness or intensity of sound. It is a logarithmic scale, which means that a small increase in decibel level represents a large increase in sound intensity. So, next time you hear someone talking about sound intensity, remember it's all about decibels!

The Science of Sound

• Low frequency sounds have a low pitch.
• Pitch depends on age and ear health.
• Ultrasound is sound at frequencies higher than most people hear.
• Sonar is used for underwater object detection.
• Ultrasound imaging creates detailed maps of internal structures.
• The Doppler Effect causes a change in sound frequency.
• Hearing and the Ear

Multiple Choice

What is the sound frequency range of ultrasound?

• 20 Hz - 20 kHz

• 20 kHz - 20 MHz

• Below 20 Hz

• Above 20 kHz

The Science of Sound

The outer ear gathers and focuses sound into the middle ear, which receives and amplifies the vibrations. The inner ear uses nerve endings to sense vibrations and send signals to the brain. Sound is recorded by converting sound waves into electronic signals that can be processed and stored. It is reproduced by converting electronic signals back into sound waves. Most musical instruments vary pitch by changing the frequency of standing waves. Resonance is the response of a standing wave to another wave of the same frequency. Sound travels fastest in solids.

Multiple Choice

What is the main function of the inner ear?

• Amplifying sound vibrations

• Converting sound waves into electronic signals

• Sending signals to the brain

• Recording and processing sound

Inner Ear: Signals to the Brain

The inner ear plays a crucial role in our hearing process. It is responsible for sending signals to the brain for sound interpretation. Without the inner ear, our brain would not be able to process and understand the sounds we hear. It is truly fascinating how our ears work in harmony with our brain to make sense of the world around us.

Sound Wave Feature: Wavelength

• In sound waves, wavelength is the distance between compressions or rarefactions.

Sound Wave Feature: Amplitude

• In sound waves, amplitude is the density of the medium's particles at the compressions of the wave.

Multiple Choice

rarefaction

• The part of a wave where the particles of the medium are farther apart.

• The distance between compressions or rarefactions

• the density of the medium's particles at the compressions of the wave

• the part of a wave where the particles of the medium are closer together.

Multiple Choice

compression

• The part of a wave where the particles of the medium are farther apart.

• The distance between compressions or rarefactions

• the density of the medium's particles at the compressions of the wave

• the part of a wave where the particles of the medium are closer together.

Multiple Choice

wavelength

• The part of a wave where the particles of the medium are farther apart.

• The distance between compressions or rarefactions

• the density of the medium's particles at the compressions of the wave

• the part of a wave where the particles of the medium are closer together.

Multiple Choice

amplitude

• The part of a wave where the particles of the medium are farther apart.

• The distance between compressions or rarefactions

• the density of the medium's particles at the compressions of the wave

• the part of a wave where the particles of the medium are closer together.

Sound Wave Feature: Frequency

• Frequency is the number of wavelengths that pass a fixed point in a second.

Sound Wave Feature: Speed

• Speed is the distance traveled by a soundwave per unit of time.

• Diffrent speeds happen depending on the medium that the sound is traveling through.

Multiple Select

Is the image Frequency or speed

• Frequency

• speed

Multiple Select

Is the image Frequency or speed

• Frequency

• speed

Effect of Medium Type on Speed of Sound Waves

The speed of sound waves is fastest in solids and slowest in gases.

• The particles of solids are close together, so the chance of energy transfer is higher in solids.

• The particles of liquids are spread out, so the chance of energy transfer is higher in solids.

• The particles in gases are far apart, so the chance of energy transfer is lower in gases than liquids or solids

Effect of Medium Temperature on Speed of Sound Waves

As temperature of the medium increases, the speed of the sound wave increases.

• As temperature increases, the particles of the medium move faster.

• The faster the particles move, the greater the chance that the particles will bump into each other.

• The more the particles bump into each other, the more energy is transferred.

Multiple Choice

The closer a sound moves toward you the _______ the frequency.

• lower

• higher

• shorter

• longer

Multiple Choice

What causes the doppler effect?

• change in speed

• change in amplitude

• change in frequency

• change in time

Multiple Choice

What happens to the pitch as the sound moves away from a person?

• lower

• longer

• higher

• shorter

Multiple Choice

What happens to the pitch as the sound moves towards from a person?

• lower

• longer

• higher

• shorter

Multiple Choice

What happens to the pitch if your are moving with the sound?

• higher

• lower

• nothing

• longer

Multiple Choice

If you are riding a train and the whistle blows, would you be able to hear the change in pitch?

• yes, you would be able to hear it everytime it changes

• no, you are moving with the train so wouldn' be able too.

• yes, doesn't matter if you are on the train or not you can hear it.

• No, it doesn't change at all.

Multiple Choice

Why do my parents think my music is to loud when I think it sounds great?

• loudness is perceived

• it is louder to them because they have better hearing

• they don't know what good music is

• pitch is to high

Multiple Choice

Why does a whisper in your ear sound just as loud as an air plane in the air?

• pitch

• closer to you

• doppler effect

• frequency

Multiple Choice

What are sound waves above the normal range of hearing?

• infrasound

• ultralight

• infralight

• ultrasound

Multiple Choice

What are sound waves below the normal range of hearing?

• infrasound

• ultralight

• infralight

• ultrasound

Multiple Choice

Why does an ambulance sound different coming towards me than going away?

• coming towards lower frequency; lower pitch

  going away higher frequency higher pitch

• coming towards lower frequency; higher pitch

  going away higher frequency lower pitch

• coming towards higher frequency; lower pitch

  going away lower frequency higher pitch

• coming towards higher frequency; higher pitch

  going away lower frequency lower pitch

Lesson 6.3
Using Sound Waves

Essential Questions:

1. In what ways does sound interact with matter?

2. How can people control sound?

3. What are some ways to use ultrasound?

Effect of Medium Type on Speed of Sound Waves

The speed of sound waves is fastest in solids and slowest in gases.

• The particles of solids are close together, so the chance of energy transfer is higher in solids.

• The particles of liquids are spread out, so the chance of energy transfer is higher in solids.

• The particles in gases are far apart, so the chance of energy transfer is lower in gases than liquids or solids

Effect of Medium Temperature on Speed of Sound Waves

As temperature of the medium increases, the speed of the sound wave increases.

• As temperature increases, the particles of the medium move faster.

• The faster the particles move, the greater the chance that the particles will bump into each other.

• The more the particles bump into each other, the more energy is transferred.

Sound waves are produced when something vibrates.

• The vibrations cause energy to transfer from one particle to another until the sound reaches the ear.

• Sound waves are longitudinal waves, which makes these waves different from ocean light, and some earthquake waves.

• Sound waves carry energy parallel to the motion of the wave.

Multiple Choice

What object uses reflected sound waves to see things underwater?

• SONAR

• echolocation

• ocean floor

• concert halls

Multiple Choice

What object uses sound waves to see things inside the human body?

• echolocation

• SONAR

• ultrasound

• infrasound

Multiple Choice

What is the process that animals use by using sound waves to find objects?

• ultrasound

• SONAR

• echolocation

• interference

Multiple Choice

What is the bending of sound waves around barrier or through openings?

• reflection

• refraction

• diffraction

• interference

Multiple Choice

Do higher or lower frequency waves diffract better?

• higher

• lower

Multiple Choice

Interference occurs when two or more sound waves _______.

• spread apart

• overlap

• move away

• stand still

Multiple Choice

When two compressions overlap making the amplitude higher and sound louder this is called...

• interference

• destructive interference

• constructive interference

• time interference

Multiple Choice

When a compression overlaps a rarefaction making the amplitude smaller and sound softer this is called...

• interference

• destructive interference

• constructive interference

• time interference