Last weekend at an honors interview at Roberts, I got to take a look in some of their physics labs. they had some fun things set up for us to check out. One thing was in a section called "physics and music". Sounds perfect for me, right? They had a bunch of wine glasses filled with different amounts of water. When you dipped your finger in some water and rubbed it around the edge of the glass, a specific note could be heard. However, if your finger isn't wet, it doesn't work. Why? Turns out, it is because there is too much friction between the finger and the glass when the finger is dry. When the finger is wet, there is minimal friction, which allows the glass to vibrate, which produces the note. The amount of water in the glass determines how high or low pitched the note is. If you try this experiment, try placing a ping pong ball in the glass. The ping pong ball will make the vibrations visible because it will move on top of the water as the glass vibrates.