Now I blew up a balloon, and rubbed it across my hair (freshly washed hair works best). Now we have a negatively charged the balloon. You can test your balloon by seeing if it will raise the hairs on your arm, if it can then your ready. If not rub the balloon more on your hair. If you don’t want to rub it on your hair, try your dog they love it.
With my balloon negatively charged and bring it closer to the cup….. The toothpick moves. The positively centered toothpick is attracted to the negatively charged balloon, which makes the toothpick rotate and swing atop the coin!
I played around with charging up the balloon and trying to move the toothpick from different distances. If I seem to charge the balloon to much or move the balloon to fast around the glass it would knock off the toothpick.
Tips: I use two US nickels for better balance and marked my toothpick in the middle with a marker to help me find the middle easier.