NEXT: Crestmead

The Most Annoying Sound In The World

WARNING: This sound is dangerously powerful; with great power comes great responsibility

Australian Curriculum links

  • Science > Physical Sciences > Year 1 > ACSSU020

You’ll need

  • 2 empty soft drink cans
  • A big breath of air

Try this

  1. Very lightly hold a can upright with your thumb resting on the bottom rim of the can, and your middle finger holding the top rim of the can.
  2. Hold the other can the same way in the other hand.
  3. Bring the two cans together until they are almost touching.
  4. Blow as hard as possible through this gap to make a high pitched squealing noise.
  5. If you don’t hear the sound, try moving the cans slightly closer together or slightly further apart. You should also make sure you are holding the cans loosely in your fingertips.

Further investigation

  • Try this experiment with cans of different sizes. How does it change the sound?
  • Try filling the cans with different materials. Examples include water, cotton wool and sand. How does this change the sound that is made?
  • Download a sound level app onto your phone and measure the level of decibels produced by this horrible noise! Who can produce the loudest sound?

What’s happening?

Blowing between the cans makes the air between them move very quickly. The two cans bounce against each other very quickly and they begin to vibrate. The small sound made by these vibrations is amplified inside the cans making a very loud, high pitched sound.