- Glasses with stems
- Food colouring
How to make it
- Half fill a glass with water, then dip your finger in it.
- Move your other hand to the base of the glass and hold firmly. Press down the rim of your glass with your wet finger.
- Slowly move your finger around the rim of the glass. You should be able to make a ringing sounds come from the glass.
- You could add food colouring to the glasses and play a colourful tune for your friends.
The glass ‘sings’ because it is being made to vibrate by your moving finger. Changing the size or the amount of water alters the sound. A big glass filled with water makes a low note, and a small glass with a little water makes a high note.
If you’d like to find out about more fun activities like this, check out Make and Do Science.