Sound

Sound Defined

• compression of PARTICLES produced when an object VIBRATES
• LONGITUDINAL wave (also called COMPRESSIONAL)
• Needs MATTER
• DIFFerent SPEED (m/s) through DIFFerent MATTER
• generally, DENSER MATTER = FASTER speed (M/S)
• exception ex.: cork SLOWER than water
• Properties of Sound Frequency Longitudinal Intensity Pitch (FLIP)

Sound Wave Increases (AMP)

• AMPLITUDE - distance wave OSCILLATES from RESTing POSITion
• HI AMP = LOUDer
• Units = DECIBels (dB)
• Humans = 0 to 120 dB
• >120 dB can injure

Frequency

• Number of WAVES in a GIVEn TIME
• hi freq = hi pitch
• units = waves (cycles) per sec = Hertz (Hz)
• HUMANs 20 – 20,000 Hz