The vibrations travel in waves away from the object. Sound Wave: a longitudinal wave caused by vibrations traveling through a medium.
Sound Waves are longitudinal (compressional) waves. The molecules are being pressed together as the sound waves move through matter. Longitudinal waves travel through the springs just like sound waves travel through the air.
Compression: the part of a sound wave where the molecules are crowded together Rarefraction: the part of a sound wave where the molecules are spread apart
Medium- a substance through which a wave can travel.
Properties of Sound frequency Pitch depends on frequency
Remember that Frequency is… the number of waves that pass by a point each second
Properties of Sound Larger frequency = higher pitch Smaller frequency = lower pitch slinky demo
High Pitch vs Low Pitch Flute http://www.youtube.com/watch?v=weTVPmWnlKE Trombone http://www.youtube.com/watch?v=bcwMovQ6US0
Notice the amplitude (volume)is the same, but the pitch changes. Low frequency Low Pitch Medium frequency Medium Pitch High frequency High Pitch how do you think opera singers can break glass when hitting high notes?
Pitch that “Hertz” hertz Pitch is measured in hertz (Hz)
Humans can hear sounds that vibrate between 20 times a second (20 Hertz) to about 20,000 times a second (20,000 Hertz).
Ultrasonic: a sound that is HIGHER than 20,000 Hz
Infrasonic: a sound that is LOWER than 20 Hz Examples: ElephantsWhales
http://ww w.youtube. com/watch ?v=AXhR mv1mrs4 Can you hear this? short clip http://www.yout ube.com/watch? v=VxcbppCX6Rk http://www.you tube.com/watch ?v=H- iCZElJ8m0 Can you hear this? medium length clip Can you hear this? longest clip