Liquid Nitrogen + Ping Pong Balls = Crazy Science Fun
This summer, Roy Lowry, an associate professor at Plymouth University in the UK tried a nice simple experiment. He poured liquified gas into a plastic bottle and closed it. This is a bad idea, Lowry warns the students in the video, because as the liquid turns into gas it will increase the pressure of the bottle. Then he put the bottle in a tank with warm water — which is supposed to make the liquid turn into gas — and filled the tank with 1,500 ping pong balls.