Sound. What makes sound? vibrations How do brass instruments like a trumpet or tuba produce sound? Vibrating air.
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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.
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