Sometimes I need a science experiment that is simple to set up, simple to do, and easy to clean up. This experiment is all that and more. It only requires two items (wine glass and water) and it can provide a long amount of fun for kids.
Mine had fun seeing who could make the loudest sound and tested how the pitch of the sound was impacted by the amount of water we put in the glass.
I hope you enjoy the experiment as much as we did.
Singing Glass Science Experiment Video
- A glass with a stem (any shape or size of wine glass will work)
Step 1 – Start with an empty glass that has a stem. Any shape or size wine glass will work.
Step 2 – Fill the glass with water. We filled it a little more than 1/2 way full. You can experiment with different amounts of water because the quantity of water impacts the pitch of the sound.
Step 3 – Get the tip of your finger wet.
Step 4 – Hold the base of the glass stem with one hand (so it doesn’t fall over) and slowly and steadily move your wet fingertip around the rim of the glass. It may take some practice, but after a while you should hear a singing noise.
How Does the Experiment Work?
Sound is a disturbance that travels through a medium as a wave. In this experiment, when you rub your finger along the rim of the glass, you disturb the particles of the glass causing them to vibrate. The vibrations in the glass are transferred to the air surrounding the glass, creating a sound wave. You can actually see the vibrations of the glass if you look closely at the water in the glass (especially where the water and the glass are in contact).
You can change the pitch of the sound produced by the amount of water you put in the glass. Pitch is how high or low sound seems to a person and it depends on the frequency of the sound wave. When you add more water to the glass, the pitch is low. This is because the high volume of water in the glass makes it more difficult for the glass particles to vibrate, so the vibrations of the glass are slower and they have a lower frequency. When you add less water to the glass, the pitch is high. This is because the low volume of water in the glass allows the glass particle to vibrate more easily, so the vibrations of the glass are faster and have a higher frequency.
Other Ideas to Try
Try this experiment again, but use different sizes and shapes of glasses. How does this affect the glass’s ability to sing? Try using a drinking glass that is made of very thick glass. How does this glass sing compared to the wine glass? Instead of using water in the glass, try a different liquid like vegetable oil or corn syrup. Does this change the sound produced by the glass?
I hope you enjoyed the experiment. Here are some printable instructions: