6th Class and Resource.
This is not one to be tried at home. A plastic bottle with a small amount of water and a large amount of air is attached to a compressor. When the pressure is to great for the modified bottle cork, the bottle takes off into the air. In the next picture, Ms Coakley has captured the stream of water that left the bottle as it took off. Talking points: Action and reaction, litres and millilitres, air resistance, power vs weight.