Sound Waves

Sound Waves

1. Key Terms

   • Waves
   • Amplitude
   • Wavelength
   • Frequency
   • Loudness
   • Pitch
   • Echo
   • Ultrasound
   • Infrasound

2. Pitch & Volume

   • The shorter in wavlength, the higher in pitch
   • The bigger the amplitude, the louder the sound

3. Microphones

   • Mobilephones and telephones contain microphones
   • These devices contain a diaphram, which does a similar job as the eardrum
   • Vibrations in the air make the diaphram vibrate, and then these vibrations are changed to electrical impulses
   • These electrical signals can then be relayed through a loudspeaker

4. Animals and sounds

   • Humans
     • 20-20,000hz
     • 90dB
   • Dogs
     • 40-60,000hz
     • 113dB
   • Elephants
     • 10-10,000hz
     • 117dB
   • Howler Monkies
     • 100-30,000hz
     • 140dB
   • Cats
     • 30-50,000hz
     • 100dB
   • Bats
     • 3000-120,000hz
     • 100dB