You can make a bottle collapse without touching it! Air pressure is all around us but you cannot feel it. It's the difference in air pressure that causes the bottle to crush.
You will need: Hot water, Cold water, Plastic drink bottle, Ice, Funnel, Bowl.
You can hear the bottle pop!
When the warm air inside the bottle cools it exerts less pressure and as the pressure is greater outside, it crushes the bottle!
![](https://i.ytimg.com/vi/thSeYzcPrqs/maxresdefault.jpg)