Sound Gr. 6 - 2018

1. Sounds
Listen carefully!!

3. Rarefaction:
air
molecules
are far apart
Compression:
air molecules
are close
together.

4. Wave structure

6. Structure of the ear
Outer ear Middle ear Inner ear
Pinna
Ear canal
Ossicles
(hammer, anvil
and stirrup)
Ear drum
Cochlea

8. Larger amplitude
Smaller amplitude
Smaller frequency
Larger frequency

9. • 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 vibrate with less force, that is
why you hear a sound quieter when its source
is further away from you.

11. 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.

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

14. 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 .

15. Videos to watch on
Youtube
• How the ear works
• https://www.youtube.com/watch?v=HMXoHKwWmU8