Echoes
Speed of sound
telephones
CDs
Computers
100
Matter that absorbs sound waves will reduce these

echoes

100

What two factors affect the speed of sound? 

type of medium the sound travels through and the temperature of the medium 

100

What do cell phones use to send signals? 

radio waves

100

How is information on sound waves stored

by pressing microscopic pits into the plastic 

100

How is sound stored in a computer? 

as digital files 

200

What is an echo? 

a reflected sound wave

200

What also affects the speed of sound? 

state of matter, fastest through solids and slower through liquids

200

what are phones good at doing? 

changing sound waves into other types of signals that can be sent over long distances.  They also change the signals they receives back into sound waves

200

what stores the digital signals that are used to recreate sound waves on a cd? 

the spiral pattern that is formed by the pits and lands

200

What's an example of a digital sound file? 

MP3

300

What are examples of animals that use echoes to hunt food? 

beluga whales, bats, dolphins
300

Sound travels faster at high or lower temperatures? 

higher temperatures- hot air faster than cold air

300

What do all telephones change sounds waves into? 

electrical signals

300

What does a CD player use to read the information on the CD? 

light

300

To record sound as a computer file, the original sound is changed into this

an electrical signal 

400

What is echolocation? 

The use of reflected sound waves to find objects

400

Sound waves reflect best of these kinds of surfaces

hard smooth surfaces

400

How do cordless phones work? 

the handset and the base change electrical signals into radio waves that they transmit to each other. 

400

What is a CD coated with so that light from a laser reflects as the CD rotates in the machine? 

aluminum 

400

After a digital file is created software reads the digital files and produces and electrical signal that is sent to these

speakers

500
What is an example of echolocation technology? 

What is sonar

500

What is reflection? 

the bouncing back of a waves when the wave hits a barrier 

500

What is the purpose of the base of a cordless phone? 

To change the radio waves back into electrical signals 

600

What is sonar? 

A type of electronic echolocation that uses echoes to locate objects underwater

700

How do animals use echoes? 

by telling how long it takes sound waves to echo back to the animal