Sound is that we can hear. We use sound to communicate and make music. We
can hear because of sound waves traveling from an object, through the air, and into our
ears. Our brains helps us what we are hearing.
Sound waves carry the energy that allows us to hear different types of sounds. Loud sounds
have more energy and a greater . Soft sounds have less energy and a smaller
amplitude. The of sound waves, or the number of vibrations per second,
provides us with pitch. Humans can hear sounds between 20Hz and 20,000Hz. Other living
things, like elephants or bats, can hear sounds much lower or much higher. Sounds that are
too low or too high for humans to hear can be used to collect . Scientists can
listen for earthquakes, take pictures of the human body, and even measure distance!
Whether we are listening to music, ringing a bell, or speaking to another person, sound
waves need to travel. The sounds we hear travel through the air, but in space there
is no air for it to travel through so any sounds made cannot be heard.
, like guitars, drums, and chimes, create sound by making something
vibrate. Instruments are tuned so that the sound waves produced are each different in size
and shape. This allows the same note to sound different depending on the instrument
chosen.
Since music is just a series of , you can use any material to make music.
Cardboard, plastic, wood, glass, and even water are all great materials for carrying sound
and making original tunes!