Page 237 - DK Children's Encyclopedia

Sound SEE ALSO

▸ ▸ Gases p.117
▸ ▸ Hearing p.127
A sound is made when something vibrates. The bigger the ▸ ▸ Liquids p.148
vibration, the louder the sound is. The faster something ▸ ▸ Musical
vibrates, the higher pitched the sound is. Sound vibrations instruments

travel through things to get to our ears. p.175
▸ ▸ Music pp.176–177

▸ ▸ Solids p.234
Sound vibrates
through the air.

The voice box Our ears detect
vibrates when the vibration
we speak, and our brain
making sound. understands
them as sound.
How sounds travel
Sounds travel by vibrating the air until it reaches
our ears and we hear the sound. The vibrations
are called sound waves. Sound waves can travel
through solids, liquids, and gases.

Volume
Volume changes depending Small, fast
on how big a vibration is. The vibrations
bigger the vibration, the
louder the sound. How high or Big, slow
low a sound is depends on vibrations
how fast something vibrates.
The faster the vibration, the
higher the sound.

Small drum Big drum
We can hit a small The big drum vibrates more
Things sound drum harder to slowly, so it has a lower note
louder when make it louder, but compared to the small drum.
they are close it vibrates at the It’s bigger, so it makes bigger
to us. same speed so it vibrations that are louder.
has a constant note.

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