Jane Wahl Kim Vredenburg November, 2001 Sounds Good to Me! Jane Wahl Kim Vredenburg November, 2001

What Is Sound? Sound is vibrations that you can hear

Sound Depends On: A vibrating source to set up the sound waves A medium to carry the waves A receiver to detect them

Vibrations Back-and-forth movement of matter or particles of matter Sound travels away from the vibrating object in all directions

Sound Waves Sound travels through matter as sound waves Particles of air are pushed together and then pulled apart Compressions are where particles are pushed together

Volume Amount of sound energy reaching your ears Depends on: How far the vibrating object is moving as it goes back and forth How far you are from the source of a sound Volume Control

Pitch How high or low a sound is Remember: The sky is high; the roots are low Depends on how fast the source of the sound is vibrating To change the pitch: Change the length of the material vibrating Change the thickness of the material vibrating

Sound Travels at Different Speeds Through Different Materials Feet per second

Which Would Be the Best Conductor? Solid? Liquid? Gas? Solid – The Bricks!

Reflection vs. Absorption Just like light waves, sound waves can be reflected or absorbed Sound waves reflect straight from a smooth, flat surface There is a clear echo Sound waves are reflected in many directions from a rough, uneven surface There is no clear echo

Your Instrument Should be: Well designed Simple Functional Attractive Creative You must be able to: Produce Sound Change Pitch Change Volume