Singing Rod

Singing Rod

Can you make aluminium sing?

What you need:

  • Aluminium rod (you can get this from a DIY store)
  • Violin or cello rosin (the sticky stuff that violinists put on their bows)

How to:

  1. Hold the aluminium rod in the centre with one hand.
  2. Dip the fingers of your other hand in rosin so they're sticky.
  3. Rub the fingers of your sticky hand from the centre of the rod to the end.

Can you hear the rod sing? You might need a bit of practice to get it really loud!

What's happening?

Sound waves are vibrations. Stroking the rod with sticky fingers causes vibrations to travel along the length of the rod. The vibrations travel to the end of the rod and cause air molecules to vibrate. The vibration of the air molecules causes your ear drum to vibrate. Your brain translates these vibrations into sound.

Different sized rods produce different vibrations, so they produce different sounds. If you rub the rod slowly, you will produce a relatively low sound. If you rub the rod aggressively, it will create an unpleasant high pitched sound.