Sound

Sound

1. Infrasound

   • 20 Hz and below
   • Below our hearing range
   • Used by elephants

2. Ultrasound

   • 20,000 Hz and above
   • Above our hearing range
   • Used by dolphins, for pregnancys and fishing boats

3. Hertz- the unit of frequency (Hz)

4. Our hearing range

   • Between 20 Hz and 20,000 Hz
   • Anything higher or lower, we can,t hear

5. Features of waves

   • Trough
     • Bottom of wave
   • Crest
     • Top of wave
   • Wave length
   • Amplitude