Blowing air into a whistle causes air to vibrate inside the whistle.
Pipe organ vibrating columns of air inside the pipes are the sound source.
Blowing air into a whistle causes a sound source.
blowing air into a whistle causes a what?
  - rapid blast of heat
  - kinetic energy
  - little beads
  - activation energy
  - sound source
  - wind speed
  - small rattling
  - mechanical