Bernoulli power is used again to make these balls move without touching them. This ‘Crazy Eperiment’ is easy to do and explores how air pressure can make things move. In fact, this is related to what happens when your car is parked on the side of the road and a bus movespast you really fast. See this connection by doing this experiment.
Measure 90cm or so of string. Tape each end to a plastic ball.
Hold the string using two hands so that the balls dangle in front of your face. Blow air between the balls as fast as you can. Try not to blow the balls, but the space between the balls. Do they move? If not, move the balls a little closer together and blow between them again.
Keep moving the balls closer together until you reach the distance where the balls move towards each other when you blow between them. At this point, they will dangle away from each other BUT will suddenly move towards each other when you blow between them.