The document discusses key properties of sound including amplitude, frequency, pitch, how it travels through different materials, and how some organisms use echo. It explains that sounds have larger amplitude and frequency when generated with more force. Pitch is determined by the length and tension of the vibrating object. Sound travels fastest through solids and slowest through air. Examples are provided of how bats and dolphins use echo to detect their surroundings. Relevant YouTube videos about sound and how the ear works are also listed.

1. Sounds

6. Larger amplitude
Smaller amplitude
Smaller frequency
Larger frequency

7. • You hear a louder sound when you hit the
drum with greater force. The drum vibrates
with more energy making the air vibrate with
more energy.
• As sounds travels a greater distance
molecules will vibrates with less force, that is
why you hear a sound quieter when its source
is further away from you.

8. Sound
bouncing
off objects
Sound will bounce
of objects, causing
echo.
Some organisms
are able to feel
their surroundings
using echo, like
bats and dolphins.

10. Sound pitch
• The pitch is how high, or
low a sound is. A child
will usually scream at a
high pitch. While a man
will shout at a lower
pitch.
• Making a vibrating
string shorter will result in
a higher pitch note.
Increasing the tension
will also increase the
pitch. Try it with rubber
bands on a tissue box .

11. Sound will travel faster in solids than
liquids, and slowest in air.

12. Videos to watch on
Youtube
• Sound video
• https://www.youtube.com/watch?v=kt1pTcfstC8
• How the ear works
• https://www.youtube.com/watch?v=HMXoHKwWm
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