Sound

What makes sound?

vibrations

How do brass instruments like a trumpet or tuba produce sound?

Vibrating air

How do woodwind instruments like a clarinet produce sound?

Vibrating reed

How do percussion instruments like drums or a piano produce sound?

Vibrating surface

How do string instruments like a guitar or violin produce sound?

Vibrating strings

Matter can be made of three different things. Name them.

Solids, liquids, and gases

What are molecules?

Type of matter too small to be seen.

What has to happen to make sound travel? (pg. F51)

Sound is caused by vibrations. When something vibrates, molecules in the air crowd

together, then spread apart, causing sound waves to travel away from the vibrating object.

Which part of the sound wave has molecules that are tightly packed

together?

compression

Which part of the sound wave has molecules that are spread apart?

rarefaction

Can you hear sounds in a vacuum? Why or why not?

No. A vacuum is a place where there is no

matter.

What is pitch?

How high or low a sound is.

How can you change the sound that a rubber band makes?

Shortening or stretching the rubber band tighter

How can you change the pitch of your voice?

Tightening and relaxing vocal cords

How can changing the rate of vibration vary the pitch of the

sound?

Faster vibrations causes higher pitches

Slower vibrations causes lower pitches

What is an oscilloscope?

Makes a “picture” of sound waves

Allows you to compare the waves of sounds that have

different pitches

What is the difference between frequency and pitch?

Frequency is the number of times an object vibrates per

second.

How is pitch related to frequency?

Higher Frequency=Higher Pitch

Lower Frequency=Lower Pitch

What is frequency measured in? What is the abbreviation?

Hertz

Hz

A frequency of one vibration per second is equal to __________.

1 Hz

What is ultrasonic?

Sounds too high to be heard by humans, but not by some

animals.

Arrange these organisms (human, bat, dog, and dolphin) in order of range of hearing, from greatest to

least.

Dolphin, bat, dog, human

What is a sound wave?

Makes the molecules of gas in the air vibrate.

What is volume measured in?

Decibels (dB)

Who was the first person to record sound? What year?

Thomas Alva Edison 1877

Describe how a microphone works?

1. Diaphragm in microphone vibrates.

2. Then coil of wire vibrates.

3. Electric current is sent to amplifier.

What are the three steps to record sound?

1. Sound waves are translated into code of 1s and 0s.

2. Tells laser beam where to cut pits into disc’s surface

3. Light is reflected onto disc’s surface and changed into sound

What is reflection?

A bouncing of a sound wave off a surface.

Name some items that reflect sound.

Wall, lockers, door

Name some items that absorb sound

Blankets, towels, sheets

Name some items that transmit sound.

Transmit means make sound.

What happens when the sound waves disappear?

Absorption

What happens to sound when it hits a hard, smooth surface such as a

wall?

Reflection

What happens to sound when it hits a soft, textured surface such as a

towel?

Absorption

Do more sound waves bounce from hard, smooth surfaces or soft,

textured surfaces?

Hard, smooth surfaces

What happens when there is too much reflection in a concert hall?

Empty, hollow sound

What happens when there is too much absorption in a concert hall?

Deadens the music

What effect did the billowy gowns and long coats have on the concert

hall?

Absorbed the sound

How are echoes made?

A sound wave reflecting off of something

At room temperature, how fast does sound waves travel?

343 meters per second

Put solids, liquids, and gases in order of the greatest speed of

sound waves to the least.

Solids, liquids, gases

Will sound travel faster through air or steel? Why?

Steel because sound travels faster through solids than

gases

Would you hear the same sound from the same distance faster in winter or in the summer? Why?

Summer because sound travels more quickly when

temperature increase.

What is sonar?

Sound navigation or ranging that uses sound waves to detect objects

far away

How do whales and dolphins use echolocation?

Bounce sound waves off objects to find out how far they are

away.

How do bats use echolocation?

Use to navigate and catch prey

How can sound be used to find the depth of the ocean?

Sound waves are sent to the ocean floor. The time is

measured for the sound waves to return and then calculated.

As an approaching police car comes at you, will the pitch get

higher or lower, and will the frequency increase or decrease?

Higher Pitch=Increases frequency

As the police car moves away from you, will the pitch get higher or lower, and will the frequency

increase or decrease?

Lower pitch=decreases frequency

What is the Doppler Effect use for?

By cops to detect speeding vehicles

Describe what quality is.

Is what makes a sound different from another

sound

Why is fundamental frequency important in designing buildings?

the vibrations build up, which can cause a building to

collapse.

What two things create a sound’s own quality?

Fundamental frequency and overtones

What is resonance?

A unique blend of the fundamental

frequency and its overtones.

How can resonance cause great damage to buildings and bridges?

Resonance can make a building rattle and sway.

These buildings could collapse.

Why are some sounds louder than others?

More energy was used to make the sounds.

What is a medium?

Matter that carries sound waves.

Sound waves can’t travel without a medium.

What is necessary for sound energy to travel from one place

to another?

There must be matter to carry it.

Can sound travel in outer space? Why or why not?

No, because there is no matter in space to vibrate.

What does the speed of sound depend on?

The medium through which the sound passes

Does the loudness or pitch of a sound change the speed at

which it travels?

NO

Do all animals “hear” in the same way that humans do?

No, some only feel vibrations.