1. Sound Energy
Making Sound

2. Success Criteria: Understand the key terms.
Learning Intention:
To understand that sound is a form of energy and be able to describe how sounds are produced and how they travel.
Success Criteria: Understand the key terms.
Sound
Vibration
Energy
Waves
Displacement
Pressure

3. When you hit a drum, the skin vibrates.
This starts a sound.
All sounds start as vibrations in materials.
Explain
SS 10

4. When you hit a drum, the air particles next to it vibrate.
The particles are squashing together and then getting further apart.
The vibrating air particles make the particles next to them vibrate.
Then these particles make the particles next to them vibrate.
The vibrating particles make up a sound wave.
Explain

5. The air particles move back and forward as the sound wave passes – this is called displacement.
As the air particles clump together and move apart the air pressure rises and falls.
The stronger the pressure change, the louder the sound.
Since sound comes from vibrating objects we know sound is a wave motion.

7. Transmission of Sound
Sound travels better in some materials than others
Sound does not travel through insulation materials.
Sound does travel through materials like water, wood and steel.

8. Musical Vibration
All musical instruments create sound by regular vibrations. Here are some animations of the ways a drum can vibrate.

9. Task: Watch the “Viewing Sounds” Video.
Investigate the sample sounds in the Audacity examples folder.
Describe each sound and draw the sound wave in your book.

10. Test your knowledge! Sounds are created by:
A) Air passing over sharp objects.
B) Movements and vibrations in air.
C) The expansion of gasses.
D) Pressure waves in air.

11. Test your knowledge! Sound moves through air as:
A) Air passing over sharp objects.
B) Movements and vibrations in air.
C) The expansion of gasses.
D) Pressure waves in air.

12. Test your knowledge! True or False: A) Sound is a type of energy.
B) The air particles move along with the sound wave.
C) High pressure is when particles are spread out.